Answer:
Step 3: exponents of the same base are added during division.
Explanation:
We have been an expression and steps used to solve the expression. We are asked to find the 1st incorrect step.
Expression:

Step 1: We will distribute the exponent as:


Step 2: Combine the exponents in denominator.


Step 3: Use quotient rule of exponents
.



Therefore, the student made a mistake in 3rd step as the exponents of the same base are added during division.