Answer:
A) = 4.
B) = 25.
C) = 4.
Explanation:
We are given that a and b are positive integers and that:

And we want to evaluate the following expressions.
Expression A)
We have:

This is equivalent to:

Therefore:

Substitute and evaluate:

Expression B)
We have:

This is equivalent to:

Again, substitute and evaluate:

Expression C)
Lastly, we have:

Note that 4 = 2². Hence:

Simplify:

Using the previous result:
