Does mass alone determine whether an object will float or sink? Explain

Which of the four major uses is predicted to change the least by 2020?

Asap many people try to eliminate fat from their diets which is one reason it is necessary for humans to eat fat a) fat is the only way to get energy b) every cell in the body must contain fat c)fat stores less energy than polysaccharides d) saturated fats make blood vessels healthier

Which environmental change would most likely result in bullfrog offspring that are able to store more water than bullfrogs in previous generations?