Our bodies are penetrated by x-rays but not by visible light. is this because x-rays travel faster than visible light?

What is relative velocity? in which condition is relative velocity known by adding the velocity of the first body and that of the second body

Unpolarized light falls on two polarizer sheets whose transmission axes are at right angles. a third polarizer is placed between the first two so that its axis makes a 52-degree angle with the axis of the first polarizer. a) what fraction of the incident light intensity is transmitted through the first polaroid? b) what fraction of the incident light intensity is transmitted through the second polaroid? c) what is the angle of polarization of the light that enters the third polaroid? d) what fraction of the incident light intensity is transmitted through the third polaroid. e) what happens if the middle polaroid is removed?

Place me with this question is my last question