Answer:
$308
Step-by-step explanation:
First, you have to find out how much it costs per pound, so you would divide 231 by 21. each pound of potatoes costs $11. so 11 x 28 would make it $308.
Volume of cone formula: V = PI x r^2 x h/3
Volume of sphere formula: 4/3 x PI x r^3
Cone: 3.14 x 9^2 x 9/3 = 763.02 cubic inches
1/2 sphere: 1/2 x 4/3 x 3.14 x 9^3 = 1526.04 cubic inches.
Total volume : 1526.04 + 763.02 = 2289.1 cubic inches
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