[Urgent]......Water is flowing at the rate of 15km/h through a pipe of diamete 14 cm into a cylindrical pond which is 50 m long and 44 m wide. In what time will the level of water in the pond will rise by 21 cm?

So,

Volume of water that flows in 1 minute =

Let the time taken to fill the pond at height of 21 cm = t minute

So,Volume of water that flows in t minute =

Now, 

Length of cuboidal pond (l) =50 m =5000 cm

And width of cuboidal pond (d) = 44 m = 4400 cm

And height of water level of cuboidal pond (h) = 21 cm

So,

So, volume of water that flows in t minute = volume of the cuboidal pond

Hence, the pond will be filled at the height of 21 cm in 2 hr.