Answer:
![3.18*10^(5)J](https://img.qammunity.org/2021/formulas/physics/college/ppzdiaywkhca6b8wi5ac4f11gniqsd5mmw.png)
Step-by-step explanation:
From the expression of workdone, we no that
Workdone= force * distance
also
force=pressure *area
since pressure = density*height* gravity
we have
work done=pressure * area * distance
from the question, the workdone will be a dependent function on the height
hence we can write
![dw=pgh*A*dh\\A=a*b\\dw=pgh*(a*b)*dh\\](https://img.qammunity.org/2021/formulas/physics/college/ouzbedg35dfpstqvm2oztukpw4xukuicvp.png)
to get the absolute workdone, we have to integrate both sides
Hence we have
![\int\limits^ {} dw\, dx =pgab\int\limits^3_0 {hdh} \, dx \\w=1000*9.8*6*12((h^(2))/(2) )|_(0)^(3)\\w=1000*9.8*6*12((3^(2))/(2) )\\w=3175200J\\W=3.18*10^(5)J](https://img.qammunity.org/2021/formulas/physics/college/xrbqrv28yusxdux5qxovovouq38kjlhg5c.png)