How are valves in the circulatory system similar to sphincters in the digestive system?

a. both limit movement of substances through the system
b. both absorb excess fluid from the system
c. both add strength to the walls of the system
d. both actively push substances through the system
e. both control an exit to the system

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.

Me plz he did not infringe upon the policy making powers that he felt the constitution gave congress. but the determination of foreign policy became preponderantly a presidential concern. when the french revolution led to a major war between france and england, washington refused to accept entirely the recommendations of either his secretary of state thomas jefferson, who was pro-french, or his secretary of the treasury alexander hamilton, who was pro-british. rather, he insisted upon a neutral course until the united states could grow stronger. which provides the best objective summary of this excerpt? president washington made a good choice when he decided not to accept the recommendations of his advisors and instead insisted that the united states stay neutral during the war between france and england as president, washington believed that the united states should remain neutral in foreign policy even though he had advisors who recommended that he take sides during the war between france and england. washington did not make policy decisions during his presidency because he did not want to interfere with the policy-making powers that the constitution gave congress. washington refused to accept entirely the recommendations of either his secretary of state thomas jefferson, who was pro-french, or his secretary of the treasury alexander hamilton, who was pro-britis

Which of the follow describes a disadvantage secondary sources have compared to primary sources?