Help me with this question for 10 points please

9514 1404 393

  (a)  10 cm

Step-by-step explanation:

Since C is the midpoint of AB, the triangle shown is 1/4 of the rectangular area shown. When the tank is sitting horizontally on its 100 cm side, the water height will be 1/4 of the 40 cm height of the tank. It will be 10 cm.

__

More elaborate explanation

Triangle area = 1/2(AD)(AC) = 1/2(AD)(1/2(AB)) = 1/4(AD)(AB)

Whole tank area = (AD)(AB)

So, the triangle area is 1/4 the whole tank area. When the tank is tipped back to horizontal, the water area will still be 1/4 the whole tank area, so will be ...

  water area = (1/4(AD))(AB)

and the height will be 1/4(AD) = 1/4(40 cm) = 10 cm

dwe

step-by-step explanation:

ewd

first one because it can't have a fraction in it

step-by-step explanation: