Answer:
Negative z-direction.
Explanation:
We need to determine the direction of the magnetic force. Since the velocity of the proton is in the positive x direction, and the magnetic field is in the positive y direction, we know by the vectorial formula 
(or, alternatively, with the <em>left hand rule</em>) that the magnetic force points in the positive z-direction (also taking into account that <u>the charge is positive</u>), so the electric field should be in the negative z-direction to balance it.
Answer:
V (initial vertical velocity) = 45.4 sin 31.2 = 23.52 m/s
1/2 m V^2 = m g h conservation of energy
h = V^2 / (2 g) = 23.52^2 / 19.6 = 28.2 m max height
Check:
t = 28.2 / 9.8 = 2.88 sec time to reach max height
h = 23.52 * 2.88 - 1/2 g 2.88^2 = 27.1 m
This is true. Gravity is constantly pulling on anything and everything (even light!), no matter how far away it is from another object.
First we need to know the equation:
F= Mass times acceleration
F = 2.0 kg times 5.0 m/s^2
multiply them to get the net force!
F= 10 N
N is newton
Hope this heps
