Answer
a, c, d) The total momentum will decrease by the spinning wheel's moment of intertia
b) To moment of inertia will decrease by the spinning wheel's moment of intertia multiplied by $\cos(30^o)$
Work Step by Step
a) There is no vertical moment of inertia and angular momentum is conserved, so the total momentum will decrease by the spinning wheel's moment of intertia
b) To moment of inertia will decrease by the spinning wheel's moment of intertia multiplied by $\cos(30^o)$
c) There is no vertical moment of inertia so the total momentum will decrease by the spinning wheel's moment of intertia
d) This will be the same as a and c holding the wheel vertically is the same as stopping it.
