The volume of the solid cylindrical iron pipe
`=(22)/(7) xx ((5.6)/(2))^(2) xx 5 c c = 123.2 c c`
Let the level of water in the gas jar be h cm .
Then the volume of water raised in the jar `= (22)/(7) xx (7/2)^(2) xx h c c = 38.5 h c c` .
As per question, `38.5 h = 123.2` or, `h= (123.2)/(38.5)=3.2`
Hence the level of water will rise `3.2` cm.