A motorboat covers the distance between two spots on the river banks `t_(1)=8h` and `t_(2)=12h` in down stream and upstream respectively. The time required for the boat to cover this distance in still water will be

Options

A. 9.6 h
B. 11 h
C. 11.8 h
D. 13 h

Explanation

To solve the problem, we need to find the time required for the motorboat to cover the distance between two spots on the river banks in still water. We know the time taken for downstream and upstream travel.

### Step-by-Step Solution:

1. **Define Variables**:
- Let \( t_1 = 8 \) hours (time taken downstream).
- Let \( t_2 = 12 \) hours (time taken upstream).
- Let \( d \) be the distance between the two spots.
...