Answer:
27a-21
Step-by-step explanation:
12a-3(7+5a)
distribute the 3
3x7=21
3x5a=15a
12a-21+15a
12a+15a=27a
-3a-21
Answer:3
The correct answer is B. (3,4)
f(x)=4+20+4
=28
6 chemicals
0.0000000861 is your answer
