Answer: choice a.
Step-by-step explanation:
1 feet = 12 inches.
Sears tower = 1450 * 12 = 17400 inches.
Now,
48 : 17400
= 2 : 725
The answer is 42.
The question is asking for angle N. We know from the question that angle N is equal to angle E (Don't think about the scale factor because it only applies to the sides. They're just trying to trick you).
To find angle E:

Move numbers to the right side:

Combine like terms:

Divide both sides by 13:

The formula for angle E:

Plug in the 8:

The angle measure of E is 42. So angle N is automatically 42 too.
To solidify, we can try to use the formula which they give us for angle N:
Zeros do not count as a sigfig so when you do something like this problem just include the numbers until you hit your significant figure limit and then substitute zeros where you can. 20000