Find the radius of the base of a cone with volume equal to 144pi in and height equal to 12

Zoe placed colored blocks on a scale in science class. each block weighed 0.8 ounces. the total weight of all the colored blocks was 12.8 ounces. how many blocks did zoe place on the scale? write and solve an equation to find the answer.

Answer this question only if you know the answer! 30 points and

Simply 8x squared + 5(7x squared- x) - 2x =