While calorie counts vary with pizza toppings and recipes, a slice of cheese pizza (weighing about 103 grams) is around 272 calories, according to LiveStrong.com. A calorie counting website averaged a slice of cheese pizza at nearly 250 calories. Indulge wisely and check out these eight pizza deals for Pi Day. Read: The Best Pi Day Jokes. Villa Italian Kitchen: Customers can get a Neapolitan cheese pizza for $3.14 with a coupon.
The Navy's nuclear-powered submarines can stay submerged for long periods of time. Air is isn't a problem as their make their own oxygen and keep the air clean. The limits on how long they can stay underwater are food and supplies. Submarines generally stock a 90-day supply of food, so they can spend three months underwater. The diesel-powered submarines (not now used by the Navy) had a limit of several days submerged.
The answer varies by species. Harbor seals can sleep underwater for as long as 20 minutes. To stay under this long, they slow their heartbeat way down. They usually only dive for three or four minutes at a time. Some seals in the Arctic (Weddell seals) spend a lot of time under the ice and can hold their breath for an hour, and maybe much longer than that. How deep do they dive? Harbor seals can dive up to 90 meters (300 feet), but they usually only go three meters (ten feet) below the surface.