The change in angular displacement as a function of time is the definition given for angular velocity, this is mathematically described as

Here,
= Angular displacement
t = time
The angular velocity is given as

PART A) The angular velocity in SI Units will be,


PART B) From our first equation we can rearrange to find the angular displacement then

Replacing,


“The term significant figures refers to the number of important single digits (0 through 9 inclusive) in the coefficient of an expression in scientific notation . The number of significant figures in an expression indicates the confidence or precision with which an engineer or scientist states a quantity.”
Regardless of what direction an object is moving, the acceleration
due to gravity is always directed toward the center of the Earth.
That's the direction commonly known as "down".