What would you add to Maslow's pyramid. Why?

Uknow what i love about i ask a dumb question it is immediately answered but when i ask a real question it take like an hour to get answered

What is the difference between total utility and marginal utility? a. marginal utility is subject to the law of diminishing marginal utility while total utility is not. b. total utility represents the consumer optimum while marginal utility gives the total utility per dollar spent on the last unit. c. total utility is the total amount of satisfaction derived from consuming a certain amount of a good while marginal utility is the additional satisfaction gained from consuming an additional unit of the good. d. marginal utility represents the consumer optimum while total utility gives the total utility per dollar spent on the last unit.

Assume the total cost of a college education will be $250,000 when your child enters college in 17 years. you presently have $69,000 to invest. what annual rate of interest must you earn on your investment to cover the cost of your child’s college education? (do not round intermediate calculations. enter your answer as a percent rounded to 2 decimal places, e. g., 32.16.)