1. Factor the expression 

2. Since
is placed in the denominator of the given expression, then 
3. Now the expression can be simplified:

Answer:
126
Step-by-step explanation:
the number of cargo cars is represented by the 35 part of the ratio , then
105 ÷ 35 = 3 ← value of 1 part of the ratio , then
passenger cars = 7 × 3 = 21
total cars = 105 + 21 = 126
Answer: A.
Step-by-step explanation:
Equation: V=lwh
5 × 10 × 15 = 750 cubic cm