80Ο/3 or about 83.775
step-by-step explanation:
since a cone is 1/3 of a cylinder, we need to find the base's area. since area = Οr^2, we get 16Ο. then, multiplying this by 5, we get 80Ο. dividing by 3, since the cone's volume is 1/3 of that of a cylinder's, we get 80Ο/3.
hope this !