Answer:
Choice A) 8.2 km
Step-by-step explanation:
Trapezoid Area
A = [tex]\frac{1}{2}[/tex]( b1 + b2)h
45.9 = [tex]\frac{1}{2}[/tex]( 8.2+ 3)h
45.9 = [tex]\frac{1}{2}[/tex]( 11.2)h
45.9 = (5.6)h
h = about 8.2
