Finding acceleration and normal force for a box pulled at 30° angle

[EnDev]

Homework Statement

http://puu.sh/25OuR

a 70kg box is pulled across a frictionlesssurface by a 300N forace at an angle of 30 degree to the horizontal

A. What is the acceleration of the box in the X direction

b. what is the normal force on the box

Homework Equations

not sure

The Attempt at a Solution

Im not sure which formula to use on this one..

 

[EnDev]

nevermind i figured it out.

A = 3.71 m/s

B 536