Answer:

Explanation:
From the question we are told that:
Far point is 
Near point is 
Therefore
Focal Length

Generally the equation for the Lens is mathematically given by



I think it was Isaac Newton
Answer:
<h2>42 N</h2>
Explanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question
mass = 7 kg
acceleration = 6 m/s²
We have
force = 7 × 6 = 42
We have the final answer as
<h3>42 N</h3>
Hope this helps you