Answer:
option D. 20 cm
Step-by-step explanation:
step 1
Find the volume of the water
The volume of the water is equal to
[tex]V=LWH[/tex]
we have
[tex]L=60\ cm\\W=40\ cm\\H=50\ cm[/tex]
substitute
[tex]V=(60)(40)(50)[/tex]
[tex]V=120,000\ cm^3[/tex] ---> volume of water
step 2
Find the deep of the water, if the tank is returned to its horizontal position
we have
[tex]V=120,000\ cm^3[/tex]
[tex]L=100\ cm\\W=60\ cm\\H=?\ cm[/tex]
where
H is the deep of the water
substitute in the formula of volume
[tex]120,000=(100)(60)(H)[/tex]
solve for H
[tex]120,000=6,000)(H)[/tex]
[tex]H=20\ cm[/tex]