A particular stimulus causes an increase in the levels of CO2 in the blood. A feedback mechanism that increases respiration rate to exhale more CO2 would be.

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

Atennis player used a tennis racket to hit a tennis ball with a mass of 0.25 kg with a force of 5.25 newtons. how does the force the tennis racket exerted on the tennis ball compare with the force the tennis ball exerted on the tennis racket? a. the force of the tennis racket on the tennis ball is equal in magnitude and opposite in direction to the force the tennis ball exerted on the tennis racket. b. the force of the tennis racket on the tennis ball is equal in magnitude and in the same direction as the force the tennis ball exerted on the tennis racket. c. the force of the tennis racket on the tennis ball is less in magnitude and in the same direction as the force the tennis ball exerted on the tennis racket. d. the force of the tennis racket on the tennis ball is greater in magnitude and opposite in direction as the force the tennis ball exerted on the tennis racket.

(10 pts! ) the major factor which causes seasonal weather changes on the earth is: a. elliptical orbit b. variation in distance from sun c. tilt of the axis d. atmosphere