Problem: Two ancient continents both had a great bird population. At some point in time, the continent of MU experienced a great drought that lasted for several years. The other continent, Lemuria, was unaffected by the drought. Which continent had fewer birds with bigger beaks that were better off?

A: MU

Problem: James lives out on the country, He wants to gather some water from a well out from behind his house. When he gets there he realizes that the wheel on the lever that pulls up the bucket is rusted which adds more friction. He decides to oil the wheel to reduce the friction. Will the ideal mechanical advantage on the lever always be less than or greater than its actual mechanical advantage?

A: greater

Problem: David is investigating the breathing process of different organisms. He found that humans have alveoli to help them with gas exchange. He got curious about other organisms that do not have alveoli. To compare these two groups he labeled organisms with alveoli as group A and organisms without alveoli as group B. Which group most likely have smaller gas exchange, group A or group B?

A: group B

Problem: David works as a nutritionist with the public health department. He categorized the certain sections of his county's population. First he categorized boys and girls between nine and thirteen years as cat A. Then he put girls between fourteen and eighteen years in cat B, and boys of the same age in cat C. Lastly, he categorized pregnant women as cat D. He needs to recommend healthy diet, especially iron intake, for each group. For which group David would recommend more iron rich foods, cat B or cat D?

A:
cat D