What dimension or dimensions do you need to know to find the volume of a sphere?

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

You deposit $5000 each year into an account earning 3% interest compounded annually. how much will you have in the account in 30 years?

Consider a bag that contains 220 coins of which 6 are rare indian pennies. for the given pair of events a and b, complete parts (a) and (b) below. a: when one of the 220 coins is randomly selected, it is one of the 6 indian pennies. b: when another one of the 220 coins is randomly selected (with replacement), it is also one of the 6 indian pennies. a. determine whether events a and b are independent or dependent. b. find p(a and b), the probability that events a and b both occur.