L'étoile Sirius est l'étoile la plus brillante lorsqu'on observe le ciel. Elle est située à environ 86 000 000 000 000 km de la Terre. 1) À combien d'années-lumière Sirius est-elle située de la Terre ? 2) Quelle durée la lumière de Sirius met-elle pour nous parvenir ?

Describe the function of the endomembrane system? what organelles are involved?

An insulated 40 ft^3 rigid tank contains air at 50 psia and 120°f. a valve connected to the tank is now opened, and air is allowed to escape until the pressure inside drops to 25 psia. the air temperature during this process is kept constant by an electric resistance heater placed in the tank. determine the electrical work done during this process.

Balloon a has charge q, and identical mass balloon b has charge 10q. you hang them from threads near each other. choose all of the statements with which you agree. check all that apply. a. a and b exert the same magnitude forces on each other. b. the force that a exerts on b is 10 times the force that b exerts on a. c. the angle between the thread supporting a and the vertical is < the angle between the thread supporting b and the vertical. d. the force that a exerts on b is 1/10 the force that b exerts on a.