Suppose a small box with a mass of 4.00kg is moving at 10.0m/s along a flat horizontal surface immediately before it begins travelling down a slope. The slope is at an angle of 20.0∘, has a length of 8.00m, and the coefficent of kinetic friction between the slope and the box is 0.750. What is the velocity of the box when it reaches the bottom of the slope?

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s. part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.