Hello I have a quiz and the time is unlimited. This sentence appeared to me.
The timer can only start after the setup process is finished.
What does this timer mean? Why does that time appear unlimited, please explain

Two polarizers are oriented at 40∘ to each other and plane-polarized light is incident on them. if only 16 percent of the light gets through both of them, what was the initial polarization direction of the incident light?

When a light bulb shines, it gives off light energy and energy. a. heat b. potential c. chemical d. electrical

Abookcase has a mass of 38 kg and the coefficient of friction between it and the floor is 0.82 what is the maximum force of friction between the bookcase and the floor a 372n b 305n c 412n d 449n