The force of friction is given by:
f = μR, where μ is the friction coefficient and R is the reaction force, which will be equal to the weight.
100 = μ x 130
μ = 0.77
Answer:

Explanation:
= normal force acting on the coin
Normal force in the upward direction balances the weight of the coin, hence

= frequency of rotation
Angular velocity of turntable is hence given as

= distance from the axis of rotation
= minimum coefficient of static friction
static frictional force is given as

The static frictional force provides the necessary centripetal force , hence
Centripetal force = Static frictional force

Well, since you only want direction, ignore the numbers. Use the right hand rule.
Current (pointer finger) points west (left).
Magnetic field (middle finger) points south (towards you).
Force (thumb) then points up (away from the earth)