Write an expression for t more than the difference of 10 and 9

Acar travels at an average speed of 56 miles per hour. how long does it take to travel 196 miles

In the geometric progression –3, 12, −48… what term is 3,072?

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?