A cylinder with a movable piston contains air under a pressure `p_(1)` and a soap bubble of radius 'r' . The pressure `p_(2)` to which the air should be compressed by slowly pushing the piston into the cylinder for the soap bubble to reduce its size by half will be (The surface tension is `sigma` and the temperature T is maintained constant).

Options

A. `p_(1) + (4T)/(r)`
B. `4p_(1) +(12T)/(r)`
C. `8 p_(1) + (24sigma)/(r)`
D. `p_(1) + (2T)/(r)`

Answer

C