Which statement best describes the overall function of the human respiratory system? A. The heart pumps blood containing carbon dioxide into the lungs, where it is absorbed. B. Oxygen is transferred into the blood, which circulates the gas throughout the body. C. Oxygen is taken into the lungs and exchanged for carbon dioxide, which is exhaled. D. Carbon dioxide is taken into the lungs and exchanged for oxygen, which is absorbed.

Suppose you have three polarizing filters, with the second at an angle of 42∘ to the first and the third at an angle of 90∘ to the first. by what perfect will the original intensity of unpolarized light be reduced to after passing through all three filters?

This is for my 8th grade science class, i really don’t understand. can someone me? , lol.

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.