First, you make a force body diagram to illustrate the problem. Then, apply Newton's laws of motion.
Summation of forces along the y-direction:
F = 0 (bodies at equilibrium) = Normal force - weight*cos45 = 0
Normal force = wcos45
Summation of forcesalong the x-direction:
F = 0 (bodies at equilibrium) = Frictional force - weight*sin45 = 0
x*Normal force - weight*sin45 = 0 (let x be the min coeff of static friction)
x*weight*cos45 = weight*sin 45
x = sin45/cos45 = 1
Therefore, the minimum coefficient of static friction must be 1.
Density is mass over volume: d=m/v
d = 393/50 => d = 7.86 g/ml
Answer:
3.2451N
Explanation:
Mass of the bullet (m) 
Speed of the bullet (V)
Rate of bullet (r) 
We can calculate with this information the average acceleration of bullets

The force is given by,

That is just because he is Superman.