McKenna was asked to write the following expression in standard form.

3−5(3a+6)
When writing the expression in standard from, McKenna made a mistake.

3−5(3a+6)
3+(−5)(3a+6) Step 1

−2(3a+6) Step 2

−6a+(−12) Step 3

−6a−12 Step 4
a. McKenna made her first mistake in ____________

Question 2
b. The correct expression in standard form is ______

basically pls fill in the blanks :]