Answer:
1.00 m/s^2
Step-by-step explanation:
The problem can be solved by using Newton's second law:

where
F is the net force acting on an object
m is the mass of the object
a is its acceleration
In this problem, F=35 N (the force applied by Amber) and

is the mass of the wagon + the brother, so the acceleration of the wagon and the brother is
