Answer:
Option A
Step-by-step explanation:
We can try to factorize all the options one by one.
For A:

We can see that the quadratic expression cannot be solved by factorization as the factors at the end of factorization are not equal in both brackets. So Option A is the correct answer for the given question.
Moreover we can also note that all the other quadratic expressions can be factorized ..
I don't quite understand the ten strategy, or what EXACTLY you're asking. But, what you can do is when you add a one digit number plus a nine, just change the nine to a ten and subtract one. It is very easy. So, 7+10 equals 17, subtract one and you get 16 which is 7+9. It is always one less than anything plus 10.
32,767/32,768 is in lowest terms and can't be reduced.
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 =) ))
Cos 70 = horizontal distance /
100 horizontal distance = 100 cos 70 = 32.2feet