Answer:
C) 
Step-by-step explanation:

Therefore, C is correct. Recall that 
Not Rationally, No. But You Can Make It Into 26.5
increase the speed is definitely the answer
Answer:
-24
Step-by-step explanation:
Easy way: 42 - 18 = 24, then translate it to negative 24 because your numbers are negative.
A little bit harder way: -42 + (-18) or -42 + 18 = -24