The ratio of the speed of sound to the average speed of an air molecule at $300 \,K$ and $1 \,atm$ pressure is close to

If an organism is in the same $Class$ but not in the same $Family$, then it may belong to the same:

The principal section of a glass prism is an isosceles triangle $ABC$ with $AB=AC$. The face $AC$ is silvered. $A$ ray of light is incident normally on the face $AB$ and after two reflections,it emerges from the base $BC$ perpendicular to the base. Angle $BAC$ of the prism is (in $^{\circ}$)

The new crop $Triticale$ was developed by intergeneric hybridization between which of the following?

$A$ gas is filled in a cylinder. Its temperature is increased by $20\%$ on the Kelvin scale and its volume is reduced by $10\%$. How much percentage of the gas will leak out?

The diagram below shows a hydraulic lift. $A$ force is applied at side $1$ and an output force is generated at side $2$. Which of the following is true?