A police officer sees the flash of a gun by the hands of terrible Tom, the burglar. 125 meters away. If the bullet travels at the speed of 585 m/s. How much time does she have to dodge it?

Can someone explain to me how to do this problem ?

The percent efficiency of a machine can never be 100% (or greater), because in the real world some energy is always converted into a. heat b. work c. input force d. output force

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?