Amy swims 500 m (0.5 km) in 6 minutes (0.1 hour). what was her speed in kilometers per hour? a. 8.3 km/hr b. 5 km/hr c. 50 km/hr d. 83 km/hr

Which of the following is the result of the nuclear weak force? the instability of large nuclei the repelling force between positively charged protons the structure of the atom certain types of nuclear decay

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?