“It’s already here, and it’s going to spread no matter what,” Martin Hicks, the mayor of tiny Grants, N.M., said after defying a state order to keep businesses closed. “It’s going to take its course like all viruses do. Why do we freak out over this?”

If she went to work, she risked bringing the coronavirus back to her great-uncle, 73, who lives with her and has health conditions.

“We need the money for sure, but I don’t want to put his life at risk just so we can have money,” she said on Thursday. “He’s had open-heart surgery, he’s got asthma, there’s no way he could come back from that. I can’t lose him.”

In places still under lockdown, the weekend is expected to bring new challenges.

In New York City, where 70-degree temperatures are expected, Mayor Bill de Blasio pleaded with residents to resist the impulse to gather outdoors. “The nice weather is very much a threat to us,” he said.

In an effort to mitigate that threat, the city’s police department said it would deploy more than 1,000 officers over the weekend to ensure that people were properly social distancing.

In New Jersey, state and county parks are set to reopen, as are golf courses. Gov. Philip D. Murphy said residents were being “trusted” with a big test, and urged people to avoid “knucklehead behavior with people ignoring social distancing.”

“If we see that again,” he said, “we will not hesitate to close the parks.”

The lifting of stringent rules across the nation signaled a significant new phase in the country’s response to the coronavirus and came even as confirmed virus cases nationally continue to grow. While the growth rate of the virus has slowed in places like New York and California, new outbreaks are intensifying in Massachusetts, Nebraska and Wisconsin, among other states.

“It’s clearly a life-or-death-sort-of-level decision,” said Dr. Larry Chang, an infectious-diseases specialist at Johns Hopkins University. “If you get this wrong, many more people will die. It’s as simple as that.”

Every evening from his kitchen table in southwestern Michigan, Representative Fred Upton, a moderate Republican running for his 18th term in office, posts a coronavirus dispatch for his constituents, highlighting his efforts to respond to the crisis and the news from Washington, often with cameos from Democrats.

“You have to sort of thread the needle,” Mr. Upton said in an interview, explaining how he has tried to navigate Mr. Trump’s performance during the crisis. “I’ve been careful. I said, ‘Let’s look to the future,’ versus ‘Why didn’t we do this a few months ago?’ I’m not interested in pointing the finger of blame. I want to correct the issues.”

It is a tricky task for lawmakers in centrist districts who understand that their re-election prospects — and Republican’s hopes of taking back the House of Representatives — could rise or fall based on how they address the pandemic.

Some vulnerable House Republicans are therefore brandishing their own independent streaks, playing up their work with Democrats, holding town-hall-style events and avoiding mention of Mr. Trump whenever possible.

One of the cruelties of the coronavirus is the way it sweeps through homes, passing from person to person, compounding the burdens and anxieties of relatives who are either prevented from giving physical and emotional care to their loved ones or risk getting sick themselves to do so.

The cruelty is starker when both partners in a couple die, often within a few days of each other. And while there is no reliable data tracking the number of couples dying from coronavirus complications, cases have cropped up across the country.

Stephen Kemp, the director of the Kemp Funeral Home in Southfield, Mich., made arrangements for 64 people who died last month of Covid-19, including three married couples.

“Entire households are becoming ill, and then the deaths of husbands and wives become a part of this crisis,” said Mr. Kemp, who has been a funeral director for 36 years. “I’ve never seen anything like it.”

There will be a derby on Saturday. Three of them, in fact. Churchill Downs is hosting a virtual Kentucky Derby, one pitting all 13 Triple Crown winners against one another in a simulated race, while Oaklawn Park will run the Arkansas Derby. Twice.

With so many horses with nowhere to run, the track in Hot Springs, Ark., is running its $1 million signature race in two divisions, each now worth $500,000.

“For them to do what they’ve done, it’s been a godsend,” said Jack Wolf, the managing partner of Starlight Racing and a co-owner of Charlatan, the morning line favorite to win the first division.

The pandemic has shut down horse racing in all but a handful of states and transformed the Triple Crown into something — no one knows what quite yet. Racing has not resumed yet in Maryland or New York, so no dates have been confirmed for the Preakness or the Belmont Stakes.

In March, the Kentucky Derby — the live one — was moved from the first Saturday in May to the first Saturday in September, after Churchill Downs officials decided that the Derby wouldn’t be the Derby without 150,000 plus fans, sporting big hats, pocket squares and clutching mint juleps.

In the meantime, the virtual Derby, billed as the Triple Crown Showdown, airs on Saturday on NBC at about 5:45 p.m. Eastern, the time slot when the live race was originally scheduled.

The loss — compared with a $21.7 billion profit during the same quarter a year ago — was driven by the pandemic’s hits to its vast array of investments and operating businesses, which expose it to huge swaths of an American economy battered by the pandemic.

That portfolio includes stakes in financial firms like Bank of America and American Express, both of which reported steep drops in earnings for the first quarter, and four of the biggest U.S. airlines. (In its regulatory filing disclosing its quarterly results, Berkshire said that paper gains or losses on its investments were “often meaningless” in understanding its overall health.)

The release comes ahead of Berkshire’s first-ever online-only annual shareholder meeting. It is a change, made necessary by the pandemic, to an event that usually draws tens of thousands of investors to an arena in Omaha, Neb., to listen to Mr. Buffett expound on the state of capitalism, business, politics and much more.

The timing and the extent of lockdown restrictions imposed to prevent the spread of the coronavirus have prompted a raft of lawsuits across the United States.

All manner of rights are being asserted. Individual rights. Commercial rights. Free speech rights. Property rights. A mariachi band is suing to get back to work.

“The constitutional and other themes are profound across the board,” said James Hodge, the director of the Center for Public Health Law and Policy at Arizona State University. “It really is becoming quite a resistance across the country to what has been the most profound use of public health power in this century.”

Initially, in March, there was a certain consensus, grudging at times, that the “police powers” granted to states gave them broad authority to impose measures to protect the public health. As stay-at-home orders stretched from weeks into months, however, those powers are being scrutinized and questioned.

Butzel Long, a suburban Detroit law firm, filed a federal case in the Western District of Michigan on behalf of five businesses seeking to reopen. “The courts really need to get involved to decide how far can a governor’s emergency authority extend,” said Daniel McCarthy, the lead lawyer.

In Los Angeles, a diverse group of small businesses including a gondola service and a pet grooming spa have sued in federal court. “We cannot keep up with the number of people who are basically crippled by this and do not understand it,” said their lawyer, Mark J. Geragos.

For decades, the fast-food drive-through has been a greasy symbol of Americana, a roadside ritual for millions of travelers with a hankering for burgers and fries.

Now, the drive-through, with its brightly colored signage and ketchup-stained paper bags, has taken on a new importance in the age of social distancing.

“For many restaurants,” said Jonathan Maze, the executive editor of Restaurant Business Magazine, “it’s an absolute savior.”

Every year, the New Bedford Whaling Museum in Massachusetts hosts a marathon reading of “Moby-Dick.” For this year’s social distancing edition, volunteers are recording performances from home.

During his lifetime, Melville was unable to sell out his first “Moby-Dick” print edition, which is over 600 pages long. But it has become an American classic, and last month the museum’s call for volunteers attracted contributors from across the United States.

Ger Tysk, a sailor, was one of them. She said social distancing was, in some ways, similar to the feeling of being out on the water with only a crew.

“I’m used to being isolated for weeks at time,” she said. “Now that people are at home and quarantined, they are kind of experiencing a similar effect to what I felt when I was isolated at sea.”

Restaurants received patrons into dining rooms partly cordoned off for social distancing, friends sought safe conversation in the sunshine, and some tried to continue a productive path forward in isolation.

As the patchwork of rules aimed at slowing the pandemic continued to evolve this week, photographers across the country documented how people were navigating social gatherings, working to preserve their businesses, fitting in outdoor pursuits like surfing and maintaining religious practices.

Remdesivir, an antiviral drug designed to treat hepatitis and a common respiratory virus, once seemed fated to join thousands of other failed medications on the pharmaceutical scrap heap. The drug had proved useless against those diseases and others and was all but forgotten by scientists who once championed it.

But on Friday, the Food and Drug Administration issued an emergency approval for remdesivir as a treatment for patients severely ill with Covid-19, the disease caused by the coronavirus.

The story of remdesivir’s rescue and transformation testifies to the powerful role played by federal funding, which allowed scientists laboring in obscurity to pursue basic research without obvious financial benefits. This research depends almost entirely on government grants.

Dr. Mark Denison of Vanderbilt University is one of a handful of researchers who discovered remdesivir’s potential. He began studying coronaviruses a quarter-century ago, a time when few scientists cared about them — the ones infecting humans caused colds, he recalled, and scientists wanted to know how they worked.

“We were interested from the biologic perspective,” he recalled. “No one was interested from a therapeutic perspective.”

Now, the F.D.A. has rushed to approve remdesivir under emergency use provisions after a federal trial demonstrated modest improvements in severely ill patients. Formal approval must come later.

How to get some crucial sleep.

Getting proper sleep is vital for physical and mental health, particularly during the pandemic. Here are recommendations for getting some.

If you didn’t get what you paid for, and the thing you bought cost five figures, it stands to reason that you would get some of your money back.

So what should students expect from colleges and universities? Answering that question requires asking another one first, which Ron Lieber does in this week’s Your Money column: What are we really paying for when we decide to pay for college?

Reporting was contributed by Julie Bosman, Nicholas Bogel-Burroughs, Joe Drape, Michael J. de la Merced, Catie Edmondson, Nicholas Fandos, Jacey Fortin, Michael Gold, Jack Healy, Gina Kolata, Ron Lieber, Neil MacFarquhar, Sarah Mervosh, Katie Rogers, Katherine Rosman, Rebecca R. Ruiz, Sheryl Gay Stolberg, Sabrina Tavernise and David Yaffe-Bellany.