So I was sick last week for 3 classes and I really missed something and don't know what im doing. Three blocks rest on a frictionless, horizontal table (see figure below), with m1 = 6 kg and m3 = 14 kg. A horizontal force F = 111 N is applied to block 1, and the acceleration of all three blocks is found to be 3.4 m/s2 (a) Find m2. For this I got M2=12kg It was wrong I did F=ma for both blocks F=6x3.4=20.4 F=14x3.4=47.6 111-20.4-47.6=42.6 42.6/3.4=12 I think I have to use gravity 9.8? (b) What is the magnitude of the normal force between blocks 2 and 3?