the number of subsets that can be created from the set {1, 2, 3} is:
3
6
7
8

What is the value of x when x + 7 = 21?

Pls as soon as ! will award brainliest and 20 ! also the answer is not 22.5 degrees! find the value of x in each case:

Taber invested money in an account where interest is compounded every year. he made no withdrawals or deposits. the function a(t)=525(1+0.05)^t represent the amount of money in the account after t years. how much money did taber origanally invested?