Brass gets discoloured in air because of the presence of which of the following gases in air? a. oxygen b. hydrogen sulphide c. carbon dioxide d. nitrogen

If scientists are wrong about earth's age based on radioactive material and the decay rates are really much faster, how would nuclear power plants be affected?

Which statement describes a way in which the digestive and excretory systems work together? a. the nephrons absorb nutrients from food going to the large intestine. b. the excretory system balances blood gases in the small intestine. c. the intestinal villi filter blood and send wastes to the bladder. d. the excretory system balances the salts and water obtained from digested food

Give three examples of plant activities that are affected by circadian rhythms and natural fluctuations in the length of daylight?