Answer:
Look below
Step-by-step explanation:

Answer B I think hope this helps
It's 12.6.
You divide 21 by the denominator, 5, and multipy that (4.2) by the numerator, 3.
You just got to plug and solve...
a³-2bc
(2)³-2(-3)(4)
Solve and you get 32!
Hopefully this helps you!!!