Answer:
Your answer is 4a+2.
5(2a+4)+a-7a-18
10a+20+a-7a-18
10+a-7a+20-18
11a-7a+2
4a+2
a)180-57-20=103
b)180-103=77
Step-by-step explanation
Question 1: 34.56 mm
Question 2: 12.57 in
Question 3: 15.70 yd
Step-by-step explanation:
19