Ayudenme por favor, con el procedimiento

Three cylinders have a volume of 2836 cm^3. cylinder a has a height of 900 cm. cylinder b has a height of 225 cm. cylinder c has a height of 100 cm. find the radius of each cylinder. use 3.14 as an approximate for π

Which of the following is not a subset of {1,2,3}?

Perry observes the opposite parallel walls of a room in how many lines do the plains containing the walls intersect