The cross-section of a well is a trapezium in shape. If the well is 15 m wide at the top and 5 m wide at the bottom and the area of cross-section is 700 sq m, the depth of well is? Choose the correct choice from the following choices.
A) 20 m  B) 60 m  C) 40 m  D) 80 m  E) 70 m
1/2 * d (15 + 5) = 700   d = 70   ANSW70 mR:70 m
<result>E</result>
The cross-section of a well is a trapezium in shape. If the well is 15 m wide at the top and 5 m wide at the bottom and the area of cross-section is 700 sq m, the depth of well is?