Answer: The value of x is 28.
Step-by-step explanation:
Since line m is parallel to line l.
So, we assume that
(3x+21)° and (4x-7)° are corresponding angles.
And we know that , corresponding angles formed when a transversal cut the parallel line are equal.
So, they must be equal to each other.

Hence, the value of x is 28.
Answer:
They are in A. P so the sum will be 2380
Polygon A,B,C,D,E and polygon L,M,N.O.K
1 mile= 5280ft
70 000/ 5280= 13.33
Therefore, in 70000 feet, there is 13.33 miles.
Hope this helps :)