Answer 1

Speed at which the water is flowing through the pipe = 15 km / h = `(15000m)/(3600s)=25/6 m/s`

Radius of the pipe= `(14cm)/2=7cm=7/100m`

Length of the cuboidal pond = 50 m

Breadth of the cuboidal pond = 44 m

Rise in the level of water in the pond =21 cm = `21/100m`

Time (in sec) taken by the pipe to fill the pond

`\text{Volume of the pond}/\text{Volume of the  water flowing through the4 pipe in 1 second}`

`=(50m xx44mxx21/100m)/(22/7xx7/100mxx7/100mxx25/6m)s`

`=7200 s`

`=7200/3600h`

`=2h`

Thus, the time taken by the pipe to fill the pond is 2 hours.