Answer:
a) 4
b) 2
Step-by-step explanation:
a) multiply the coefficients and add the exponents
(4)(1) ·
= 4
b) divide the coefficients and subtract the exponents
(14 ÷ 7) ·
= 2
The answer is: 
The explanation is shown below:
1- You have the following expression given in the exercise:

2- When you multiply signs, you obtain:

3. Now, you must add like terms, as following:

4. Therefore, you have that the expression simplified is:

B, 4% .
Find this by using the Interest Formula:
I = P X R X T
I = 7500 X .OO4 X 3
I = 900