The answer is option 2,
2x10^10
you don't need to know this for real life situations but for school you do need to know it, i dont know how to do this but here's a link to the same question you have but it's explained on how to solve it
https://www.wyzant.com/resources/answers/499729/fireworks_can_go_up_to_1000_feet_in_around_3_seconds_what_s_is_it_s_average_vertical_speed_in_feet_per_second_and_miles_per_hour
((Also i'm a fellow ARMY as well =) ))
Factor by grouping.
(7x+2)(x-2) I think not sure
The rule to convert a mixed fraction to an improper fraction is
Here in 
Here a = 422, b = 8 and c = 100
Now a × c = 422 × 100 = 42200
And 42200 + 8 = 42208
So we have
This fraction can also be reduced as
Hence
