For the following questions answer them individually
Minimum depth of ballast cushion for a Broad ‘ Gauge wooden sleeper of size $$275 \times 25 \times$$ 13 cm with 75 cm sleeper spacing is
The minimum dissolved oxygen which should _ always be present in water in order to save the aquaticlife is
Theratio of flexural rigidity of a beam $$(b \times d)$$ to anotherone $$(b \times 2d)$$ of similar material will be