Answer:
D
Step-by-step explanation:
:)
None of the above is the correct choice
ANSWER
A. 1/9
EXPLANATION
When we have an expression with a negative exponent we can solve it by "flipping" the fraction and solving with the positive exponent:

In this problem we have to find:

We can think of a whole number as a fraction whose denominator is 1:

So we can use the trick:

And solve:
The rate of trip 2 is 5 km/h
The time of trip 1 is 0.9-x hours