Someone help fast please

Which of the following is an example of a rational number? a. π b. √ 9 c. √ 8 d. 3.8362319

Plz hurry finals a paper cup in the shape of an inverted cone is 8 inches tall and has a radius of 1.5 inches. how much water can the cup hold? use 3.14 for pi. round the answer to the nearest tenth. a) 12.6 cubic in. b) 18.8 cubic in. c) 37.7 cubic in. d) 56.5 cubic in.

0.75,1.75,2.75,3.75 is arithmetic or geometric?