Explanation:

Certainly! Let's break down the problem:

- The boat's speed in still water + current speed = 20 km/hr.

- Upstream speed is reduced by the current, thus slower.

- Time taken upstream = 8 hours.

- Distance upstream = 96 km.

- Upstream speed = distance/time = 96 km / 8 hours = 12 km/hr.

- Let the speed of the boat in still water be 'b' and speed of current be 'c'.

Equation 1:

\( b+c = 20 \)

Equation 2 (upstream speed):

\( b-c = 12 \)

- Solving these equations:

1. Add Equation 1 and Equation 2:

\( (b+c) + (b-c) = 20 + 12 \)

2b = 32

b = 16 (speed of boat in still water)

2. Use the value of b in Equation 1:

\( b+c = 20 \)

16 + c = 20

c = 4 (speed of current)

- Difference between the boat's speed and the current's speed is \(16 - 4 = 12\) km/hr.

- Options:

- Option:1, 10km/hr

- Option:2, 14km/hr

- Option:3, 16km/hr

- Option:4, 12km/hr

- Option:5, 18km/hr

- Correct Answer: Option 4: 12 km/hr