D. the force is doubled and the object’s mass is halved? 18. ||| a man pulling an empty wagon causes it to accelerate at 1.4 m/s2. what will the acceleration be if he pulls with the same force when the wagon contains a child whose mass is three times that of the wagon?

Explanation:

Let say the empty wagon has mass "M"

now by newton's II Law we will have

now it is given that empty wagon is pulled with acceleration 1.4 m/s/s

now we will have

now a child of mass three times the mass of wagon is sitting on the empty wagon

so here we have

so we have

c

explanation:

i believe the answer is c and this is only worth 10 points you might wanna change it

the independent variable, or the one that is intentionally manipulated is the speed.