Answer:
A (first picture)
Step-by-step explanation:
Based on the picture, the lines are both perpendicular and the red line splits AB into two equal parts (bisects it), so it must represent the perpendicular bisector of AB.
a = length
b = height(width)
a=3b
2(a+b)=120
2(b+3b)=2(4b)=8b
8b=120
b=15
a=45
length is 45 feet
width is 15 feet
cos O = adjacent / hypotenuse
cos O = 12/13
I hope I helped you^_^