The valves of the heart and veins are similar in that they both: A.) Prevent blood from flowing too quickly.

B.) Are made of rigid cartilage.

C.) Prevent backflow of blood.

D.) Act as propellers to move blood forward.

(8%) problem 12. a bowling ball of mass mb 3 kg 's rolled down the lane with a velocity ofy-2/ m s lt strikes a single remaining pin mp 0.93 kg head on. after the collision the bowling ball has a velocity (in the same direction) of v2 1.1 m/s. = ▲ 33% part (a) write an expression for the velocity of pin in the horizontal direction after the impact, im ,, 33% part (b) what is the pins speed in ms? 33% part (c) assuming the coefficient of friction s μ,-0.1. how far in meters could the pin slide before stopping if it doesn't topple?

When doing scientific research ,the sources used should be ?

While preforming an experiment involving a reaction between two chemicals the scientist observes that the reaction container has become warm the observation is an example of