The voltage of clouds is 4* 10^6 V with respect to ground. In lightening strike lasting 100 ms a charge of 4C is delivered to the ground. The Power of lightening strike is (the ans is 80 MW and not 160MW but how???)

we know that

power is given as the rate of doing work

so,

P = W/t

here, the work done is given as the product of charge (q) and potential difference (V)

W = qV

so,

P = qV / t

here,

q = 4C

V = 4x10⁶ volts

t = 100ms = 0.1s

so,

P = (4x4x10⁶) / 0.1

thus,

P = 160x10⁶ W = 160 MW
As per my understanding this should be the answer.

Recheck your answer.

Regards