Joe is measuring the time it takes for a ball to roll down a ramp. in this experiment joe takes the measurement 5 times and gets the following results: 24.8, 23.9, 26.1, 25.1, 24.5 seconds. joe uses the standard deviation of these numbers as the "margin of error" on his measurement. does joe's average time agree with the accepted value of 25.9 seconds, within his margin of error? can anyone me with this?

The density of a liquid could be found by using

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?

What’s #16 asking me and how do i solve it?