I think it might be c hope that helps you
1st is parallel
2nd is perpendicular
3rd is perpendicular
4th is perpendicular
Answer: 20 mph
Explanation:
Speed is a physical quantity which is equal to the ratio between the distance covered (d) and the time taken (t):

In the first part of the problem, the plane flew a distance of d=400 mi in a time of t=2.5 h. The speed of the plane in this case was the difference between the proper speed of the plane, v, and the speed of the wind, w, since the plane flew opposite to the wind. So we can write:
(1)
During the return trip, the plane flew with a speed (v+w), since the wind was on the tail, and it took 2 hours to cover the same distance:
(2)
So we have two equations with two unknown variables. From (1), we get

Substituting into eq.(2)

So, the speed of the wind was 20 mph.
Answer:
3(n-5)
Step-by-step explanation:
Less than indicates subtract and since 5 is less than a number <em>N</em> goes first.
Tripled goes on the outside because the number that is 5 less gets tripled
Hope this helps
Its the last one (the only one that applies to the first rule).