Answer: Option A

Explanation:

Gain in 1 year = Rs. 112.50

Answer: Option D

We need to know the S.I., principal and time to find the rate.

Since the principal is not given, so data is inadequate.

Answer: Option C

Let the principal be P and rate of interest be R%.

S.I. for 3 years = Rs. (12005 - 9800) = Rs. 2205.

Principal = Rs. (9800 - 3675) = Rs. 6125.