A vessel used to sell kerosene is a frustum with upper radius and bottom radius 1 cm and 2.1 cm respectively. The height of the frustum is 21 cm. But a dishonest shopkeeper makes a hemispherical inward bump in the vessel with same radius as base. If he could have honestly made 60% profit, what is the profit (%) he makes by cheating? (Approximated to the nearest integer)

A vessel used to sell kerosene is a frustum with upper radius and bott

1.	A vessel used to sell kerosene is a frustum with upper radius and bottom radius 1 cm and 2.1 cm respectively. The height of the frustum is 21 cm. But a dishonest shopkeeper makes a hemispherical inward bump in the vessel with same radius as base. If he could have honestly made 60% profit, what is the profit (%) he makes by cheating? (Approximated to the nearest integer)
A.	61
B.	67
C.	71
D.	75
E.	77
Answer» C. 71