Correct the following statement, wherever necessary.

(a) Volume of a gas is inversely proportional to its pressure at constant temperature.

Correct the following statement, wherever necessary.

(b) Volume of a fixed mass of a gas is directly proportional to its temperature, pressure remaining constant.

Correct the following statement, wherever necessary.

(c) $0°\mathrm{C}$ is equal to zero Kelvin.

Correct the following statement, wherever necessary.

(d) Standard temperature is $25°\mathrm{C}$.

Correct the following statement, wherever necessary.

(e) Boiling point of water is $273 \mathrm{K}$.