Answer:
9 units
Step-by-step explanation:
By the midsegment theorem,

Since the ratio
then
and

Draw two heights LE and MF. Quadrilateral ELMF is a rectangle, then EF = LM = 6 units.
Trapezoid KLMN is isosceles trapezoid (KL = MN), then KE = FN and

Consider right triangle KLE. By the Pythagorean theorem,

1:4 because both numbers can be divided by 64.
C-7 hours, 0 minutes because between 8 and 11 are 3 hours and between 12 and 4 are 4 hours. 3+4= 7 hours