Answer:
The available balance in the bank for lending is 4000.
Explanation:
It is given that the required reserve ratio is 20 percent and a customer deposited 5,000.
It means the 20% of 5000 must be save as required reserve ratio and the remaining part is the available balance in the bank for lending.

It means the reserved amount is 1000. The available balance in the bank for lending is

Therefore the available balance in the bank for lending is 4000.