Q1: The weight of a good quality brick when immersed in water for a period of 16 hours should not exceed the weight of dry brick

ANS:A - 20%

1st class brick in immersed 24 hours, water absorb is 20% but good quality brick is 15% absorbed in dry weight of a brick. For 24 hr percentage, I'm increasing by weight is 25-35appro.
And so for 16 hours 20percentage. A brick is taken and it is weighed dry. It is then immersed in water for a period of 16 hours. It is weighed again and the difference in weight indicates the amount of water absorbed by the brick. It should not in exceed 20 percent of the weight of a dry brick.