A group of bike riders took a 4 hour trip. During the first 3 hours, they traveled a total of 50 km, but during the last hour they traveled only 10 km. What was the group's average speed for the entire trip?
A. 60 km/hr
C 30 km hr
B. 40 km hr
D. 15 km hr

In which scenario is the least amount of work done on a crate? a force of 120 n moves it 25 m. a force of 115 n moves it 26 m. a force of 130 n moves it 22 m. a force of 125 n moves it 27 m.

Arotating space station is said to create “artificial gravity”—a loosely-defined term used for an acceleration that would be crudely similar to gravity. the outer wall of the rotating space station would become a floor for the astronauts, and centripetal acceleration supplied by the floor would allow astronauts to exercise and maintain muscle and bone strength more naturally than in non-rotating space environments. if the space station is 200 m in diameter, what angular velocity would produce an “artificial gravity” of 9.80 m/s^{2} 2 at the rim?

Astudent weighing 700 n climbs at constant speed to the top of an 8 m vertical rope in 10 s. the average power expended by the student to overcome gravity is most nearly