Answer:
(a) 
(b) 
Explanation:
Given data
The angular velocity of two cylinders ω=257 rad/s
The mass of the two cylinders m=2.88 kg
The radius of small cylinder r₁=0.319 m
The radius of larger cylinder r₂=0.605 m
For Part (a)
The rotational kinetic energy of the cylinder is given by:

Where I is rotational of inertia of solid cylinder about its central axis.
So

Substitute the given values
So

For Part (b)

Substitute the given values

Being the planet closest to the sun, Mercury must be the one
with the shortest year. That's how gravity works.
Answer:
speed equals distance over time 50 divided by 5.
an element can make a molecule. so technically yes.
Check the 1st 2nd 3rd and 4th boxes