Answer:
D. 
Step-by-step explanation:
The given equation is

When we divide through by 4 we get;

Comparing to
y=mx+c,
The y-intercept is 
The corrrect choice is D.
Siny/2.7=sin63/2.8
siny=2.7sin63/2.8
y=arcsin((2.7sin63)/2.8)
y≈59.23° (to nearest one-hundredth of a degree)
The problem statement gives you the relationship between their speeds, and it gives you information you can use to find their total speed. You solve this by finding the total speed, then the proportion of that belonging to Bill.
The total speed is (120 mi)/(3 h) = 40 mi/h.
The speed ratio is ...
... Bill : Joe = 3 : 1
so the speed ratio Bill : Total is ...
... 3 : (3+1) = 3:4.
Bill's speed is (3/4)×(40 mi/h) = 30 mi/h.