01.07 operation scientific notation

Carter drank 15.75 gallons of water in 4 weeks. he drank the same amount of water each day.a. estimate how many gallons he drank in one day.b. estimate how many gallons he drank in one week.c. about how many days altogether will it take him to drink 20 gallons?

Acoin bank containing only dimes and quarters has 12 more dimes than quarters. the total value of the coins is $11. how many quarters and dimes are in the coin bank?

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie