633,600 ft. per hour I used a calculator converter so its a 100% right
Answer:
Variable
Step-by-step explanation:
If you can substitute a unknown variable with another expression that is equal, you can then solve for another variable, and with that equal expression, solve for the first variable.
Ummmmm lets see.... 1? Because then 3 times 1 is 3 + 3 = 9 so that's the only answer that works