The initial blank diameter required to form a cylindrical cup of outside diameter ’d’ and total height ‘h’ having a corner radius ‘r’ is obtained using the formula

A

$$Do = \sqrt{d^2 + 4 dh} - 0.5r$$

B

$$Do = d + 2h + 2r$$

C

$$Do = d^2 + 2h^2 + 2r$$

D

$$Do = \sqrt{d^2 + 4 dh - 0.5r}$$