For this case we have that by definition it is fulfilled:

Where:
a: It is the base
b: It is the exponent
So, if we have the following expression:
-6 to the power of 4, is equivalent to: 
So we have to:
-6: It is the base
4: It is the exponent
Answer:
-6: It is the base
4: It is the exponent
PLUG in the numbers
4.5=500 x R x 2.5
divide both sides by 500
0.009=R x 2.5
divide 2.2 to both sides
R=.0036
In percent you have to multiply by 100 which is 0.36%
The domain is the corresponding value of x
so, as shown at the graph :
The line starts at x =