An electromagnetic wave of intensity $I$  falls on a surface kept in vacuum and exerts radiation pressure $p$ on it. Which of the following are true?

When electromagnetic radiation of an intensity 𝐼 is incident on a perfectly reflective surface, the radiation pressure 𝑃 exerted on the surface is given by

$P=\frac{2I}{c}$ , where,  𝑐 is the speed of light.

When electromagnetic radiation of an intensity 𝐼 is incident on a perfectly absorbing surface, the radiation pressure 𝑃 exerted on the surface is given by

$P=\frac{I}{c}$ , where,  𝑐 is the speed of light.

For other surfaces, 

$\frac{I}{c}<p<\frac{2I}{c}$