A 4.8 kg skateboard and a 68.3 kg rider reach the bottom of a 5.2 m long, 13 degrees hill, where she smoothly grabs her 6-kg bag from the ground. If friction effects can be modeled with a coefficient of 0.125, what is her speed after picking up the bag?

Based on the concept of the wave-like nature of light, huygens' theory of light postulates that the more light was "bent" by a substance the slower it would move while traversing across that substance. a) deflection b) interference c) refraction d) resonance

Most of the volume of an atom is occupied by the

An astronaut on the moon throws a baseball upward. the astronaut is 6 ft, 6 in. tall, and the initial velocity of the ball is 3030 ft per sec. the height s of the ball in feet is given by the equation s equals negative 2.7 t squared plus 30 t plus 6.5s=−2.7t2+30t+6.5, where t is the number of seconds after the ball was thrown. complete parts a and b.