A car is travelling with a velocity 90 km/hr and other with 72 km/hr in opposite direction, find the relative velocity between them

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

4. if you were an astronaut on the moon, what would you experience? what would you see from your perspective?