answer: 197.92 square inches
step by step:
volume of a cone is V=πr^2h/3
1. divide diameter by 2 to find radius
r = diameter/2
r = 6”/2
r = 3”
2. plug in known values of r and h to find V
V = πr^2h/3
V = π(3”)^2(21”)/3
V = π(9”)(7”)
V = 197.72 square inches
