The cross-section of a water channel is a trapezium in shape. If the channel is 14 meters wide at the top and 8 meters wide at the bottom and the area of cross-section is 990 square meters, what is the depth of the channel (in meters)?
Choices:
A) 50 B) 60 C) 70 D) 80 E) 90
1/2 * d * (14 + 8) = 990   d = 90   The answer is 90.
<result>E</result>
The cross-section of a water channel is a trapezium in shape. If the channel is 14 meters wide at the top and 8 meters wide at the bottom and the area of cross-section is 990 square meters, what is the depth of the channel (in meters)?