What are brown bears doing as a result of panting? maintaining internal water levels by releasing moisture
maintaining internal water levels by taking in moisture
maintaining body temperature by warming up
maintaining body temperature by cooling down

On a cold day, when the air temperature is 0°c, you empty your lungs and take a deep breath, filling your lungs with 4.2 l of air. if you hold your breath until the temperature of the air in your lungs reaches 37°c, what is the volume of the air in your lungs at that point, assuming the pressure does not change?

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?