What is the acceleration of a 10kg object, if the net force acting on it is -4.2n

We know, F = ma
Here, F = -4.2 N
m = 10 Kg

Substitute their values, 
-4.2 = 10 * a
a = -4.2 / 10
a = -0.42 m/s²

In short, Your Answer would be -0.42 m/s²

Hope this helps!

That would be the corect answer hope this