Respuesta :

Answer:

9.8J

Explanation:

The work done by the friction force can be calculated as

W = Fd

Where F is the friction force, and d is the distance that the block slide.

So, replacing F = 1.4 N and d = 7 m

W = (1.4N)(7 m)

W = 9.8 J

Therefore, the work done by the friction was 9.8J against the movement of the block