Question

A conical paper cup has a radius of 2 inches. Approximate, to the nearest degree, the angle β so that the cone will have a volume of 20 in^3

Answer 1

volume = area of base *height 

20 = pir^2 *h

20 = 3,14*4*h

h = 20/12,56 = 1,59 rounded 1,6

- using the triangle formed by radius,the height of cup and the slant height of cup so we can writing that

tan ß = h/r so tan ß = 1,6/2 = 0,8

tan ß = 0,8 so ß = arctan 0,8 = 38,6 degrees so 39 degrees 

hope helped