The period of oscillation of a simple pendulum is `T= 2pisqrt(L'/'g)`. Measured value of L is 20 cm known to 1 mm accuracy and time for 100 oscillations of the pendulum is found to be `90 s` using a wrist watch of Is resolution.What is the percentage error in the determination of g ?
Options:
(a) 5%
(b) 3%
(c) 4%
(d) 7%