Idon't understand this question can you me

Hey free points ! people i have a few math questions on my profile consider looking at them i have to get done in 30 mins!

When a 757 passenger jet begins its descent to the ronald reagan national airport in washington, d.c., it is 3900 feet from the ground. its angle of descent is 6 degrees. how far must the plane fly to reach the run way? a. 37,106 ft b. 37,310.4 ft c. 23,456.6 ft d 2,492.7 ft

What is the y-intercept of the line with the equation 3x + 4y = 12?