A. 22/7 x 24/35
Feedback Since level of water increased in cylinder by height 4.
This is because of the rectangular block .
Therefore , area of rectangular block immersed in water is
= 22/7×6×6×4
Thats why portion of block immersed in water is
= (22/7 * 36 * 4) / total vol. of rectangle
= (22/7 * 36 * 4)/ (7*5*6)
= (22/7 * 24)/ 35.