The Kentucky Derby is the biggest horse race in America, and preparing for it takes millions of dollars and thousands of people. We went to Churchill Downs days before the big race to see what it takes to train the winning horse and prepare the century-old track for 400,000 fans.
Correction: An earlier version of this story misstated the amount of feed Acipenser produces each month. It is about 60 metric tons per month, not kilograms. Business Insider also misstated that Acipenser released male Sturgeon into Lake Mantasoa. This has been removed.
The bulletproof Cybertruck is perhaps Tesla's biggest gamble to date. It's not clear if Elon Musk will be able to sell enough of the $100,000 vehicles to break even — or if he'll even be able to sell them at all outside the United States.
Tunnels have run under Gaza for decades. But when Hamas took over, the underground network expanded into what Israel calls its biggest military threat. We decoded the long history of the Gaza tunnels to find out what makes it so hard to destroy.