The energy from the movement of electrons through the electron transport chain is directly used to synthesize atp.

that would be b i just took the test : )

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west

3. dark matter

empty space could also be a simple vacuum