The formula for force is F=MA (Force = Mass x Acceleration). We will use this formula to help solve the question.
I will go along with the formula as I write out the question to make it more understandable.
Calculate the force (F=) of a 300kg truck (Mass x) accelerating at 0.5 m/s^2 (Acceleration).
Now that we've written it out, let's only put what we have in the parenthesis.
F=300kg x 0.5 m/s^2.
Multiply 300 by 0.5.
We get 150N.
Your answer is 150N.
I hope this helps!