Let me try:
Normal force= 169.74N
Coefficient of kinetic friction= 0.577
Explanation
a. For a given inclined plane, normal friction is equal to the force perpendicular to the plane which is equal to
mgcos theta = 20×9.8× cos30 = 169.74N
b. The coefficient of kinetic friction for an inclined plane is given as
tan theta =tan 30 = 0.577
It was super heated to turn in to a liquid
Answer:
(a) θ= 43.89°
(b) 

Explanation:
Ball 1:

Ball 2:

As the collision is elastic, it means that kinetic energy and momentum are conserved. Following that, we apply the law of conservation of energy and momentum:

and

Where u is the velocity before the collision, and v are the velocities after the collision. Both previous equations can be simplified as:

and

This because the two balls have the same mass. We know that the cue ball is deflected and makes an angle of 30°. From conservation in x-direction, we get::

and

Solving we get:

From conservation in y-direction, we get:

From this, we solve this equation system and get the answers. Remember to add 30° to the angle obtained.