Answer:
a. 
b. 
Explanation:
I have attached an illustration of a solid disk with the respective forces applied, as stated in this question.
Forces applied to the solid disk include:

Other parameters given include:
Mass of solid disk, 
and radius of solid disk, 
a.) The formula for determining torque (
), is 
Hence the net torque produced by the two forces is given as a summation of both forces:

b.) The angular acceleration of the disk can be found thus:
using the formula for the Moment of Inertia of a solid disk;

where
= Mass of solid disk
and
= radius of solid disk
We then relate the torque and angular acceleration (
) with the formula:

Answer:
Pressure = 5 x 10⁶ Pa
Explanation:
Given:
Height of building = 512 m
Find:
Pressure
Computation:
P2 = P1+dgh
P2 = 1 + (1000)(9.8)(512)
P2 = 51.2 atm
Pressure = 5 x 10⁶ Pa
Classically, gravitational attraction is due to the masses of objects. It is inversely proportional to the square of the distances between the objects.
Magnetic attraction is due to the magnetism in objects which is due to uncompensated electron spins in certain atoms. The force due to magnetism less easy to put into one equation than gravity since magnetic fields can have different shapes, but the simplest one (the dipolar field) is inversely proportional to the cube of the distance between the magnetic dipoles.
The correct diagram is B:)