What is 2.65 as a fraction? and -0.225 as a fraction?

The area of an extra large circular pizza from gambino's pizzeria is 484 pi cm squared . what is the diameter of an extra large pizza from gambino's pizzeria?

Just tell me how to set up the equation.

Suppose a laboratory has a 30 g sample of polonium-210. the half-life of polonium-210 is about 138 days how many half-lives of polonium-210 occur in 1104 days? how much polonium is in the sample 1104 days later? 9; 0.06 g 8; 0.12 g 8; 2,070 g