A ball is thrown into the air with a speed of 32 feet per second. The function h = 32t - 16t2 models the height of the ball after t seconds. How many seconds does it take for the ball to reach its maximum height?

The depth of a lake at a certain point, wich is a function of the distance of that point from shore, is 30 feet.

I’m really confused and need your assist me with this question i’ve never been taught

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?