Earth has been sending out radio messages for about 115 years, so detection equipment on a hypothetical planet 115 light-years away might just now begin receiving them. What is the parallax angle subtended by a system at this distance

Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i.e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.

Achild has maximum walking speed of 1.6 m/s. what is the length of the child's legs? 0.26 m

You notice the birds sitting on the electrical wires which of the following explain why the birds don't get shocked