Would some please check these and see if I am doing them right thank you

1. Gasoline is about $2 per gallon. You use about 1 1/2 gallons each day driving to and from work. How much should you budget for gasoline over the next month (about 20 workdays)?

Answer 1 1/2 x $2.00 = $3.00 a day
20 day x $3.00= $60.00

2.Four buttons have diameters of 5/8 , 3/4 ,9/16 , and 7/8 inches. Which button is smallest?
Answer: B) 9/16

3. If the base of a parallelogram is 6 1/2 in. and its height is 1 1/2 in., what is its area?

6 1/2 x 1 1/2 = 13/2 x 3/2 = 39/4= 9 3/4

4. A triangle has base 15 feet (ft) and an altitude of 4 ft. Find its area.

1/2 x 4ft x 15ft= 30ft^2

5. The circular surface of a table has a diameter of 4 ft. What it will cost to have the top refinished if the company charges $5 per square foot for the refinishing? Use 3.14 for piƒnand round your answer to the nearest cent.

A= 3.14 x 4ft/2^2
3.14 x 12^2
3.14 X 24
75.36ft

Please do not double-post the same questions