Aperson is trying to judge whether a picture is properly positioned by temporarily pressing it against a wall. the pressing force is perpendicular to the wall. the coefficient of static friction between the picture and the wall is 0.660. what is the minimum amount of pressing force that must be used?

Answer: fn = wcos50 = 38.89(9.81)(cos50) = 245.23 n

As newton's first law states a object in motion stays in motion

Sounds propagates through some kind of medium. usually it's air, but it goes just as well through solid objects like walls, windows etc. a soundwave will compress the (air)molecules in front of it, and if this increased density wave hits your ears, you register it as sound. solid objects like walls are a lot denser than air, this means that they will damp a wave, but also carry it easier.

The answer is b. cellular respiration