Can anyone tell me if these are right?

All but one describes an effect of aging on the digestive system. a) decreased acid secretion b) decreased elasticity of stomach c) capacity to resist damage decreases d) food remains in stomach for less time

Sarah and john are having a discussion on genetic diversity. sarah believes that it happen over a long period of time. john it happens immediately. who is correct? a. sarah is correct because genetic diversity occurs over a long period of time. b. john is correct because genetic diversity occurs immediately. c. both are correct because genetic variation can occur or long period of time. d. neither are correct because genetic diversity occurs over any period of time

9. the history of life on earth is recorded in