Me! i really don't understand physics. ( explain how you got the answers also) you!

P = Momentum
M = Mass
t = time
v = velocity (speed)
J= Impulse

1.)
F = 100N
t = 5s

Change in momentum(P) = Ft

I see that this is not one of your equations but your equations do not work with this problem.

P = Ft
P = (100)(5)
P = 500 Ns

2.)
See if you can get this one by yourself from what I did on the last problem.

3.)
P = 25 kgm/s
M = 2.0 kg

So, you are looking for velocity (speed). Look for the equation that has momentum, mass and velocity.

Use the equation P = mv

25 = 2(v)
25 = 2v
25/ 2 = 2v/2
12.5 m/s = v

4.) Do the same for number 4.
P = 12 kgm/s
M = 1kg

P = mv
12 = 1v
12/1 = 1v/1
12 m/s = v

6.)
P = 100 kgm/s
V= 7.0m/s

P= mv
100 = m7.0
100/7 = 7.0m/7
14.28 kg = m

Try page 2 by yourself and message me or comment if you need more help. Just identify the variable you have and what you need to find and put them in an equation that fits. You can do this