Answer:
The acceleration is 2 m/s2.
Explanation:
We calculate the acceleration (a), with the data of mass (m) and force (F), through the formula:
F = m x a ---> a= F/m
a = 40 N/20 kg <em> 1N= 1 kg x m/s2</em>
a= 40 kgx m/s2/ 20 kg
<em>a= 2 m/s2</em>
You can find the mass of an atom by adding the number of protons and neutrons. In this case the atom has 2 protons and 3 neutrons so the mass is 5.