Problem: Mike was reading about climate change. The author compared two different time periods, era A and era B. Era A was set in the present day. But era B was set in the year 2040. Mike was surprised to find how Arctic area would change in the coming years. Would less or more fresh meltwater enter the north Atlantic in era A than in era B?

A: less

Problem: Mike grew tomatoes on his parcel of land and so did John. Mike's attempt was very successful, because he adjusted the soil's pH to a viable level for growing vegetables, and John didn't. Both parcels had soils with lots of sodium carbonate in them. John's experiment failed. Which soil had less unfavorable physico-chemical properties?

A: Mike's

Problem: Keith is a doctor in a local hospital. Today, he is seeing three patients, patient A, patient B, and patient C. Patient A has been suffering from hepatitis B all his life; patient B is recovering from hepatitis B on his own; and patient C doesn't have hepatitis B. Keith would now compare the symptoms of these patients. Which patient would less likely risk a damaged liver, patient A or patient B?

A: patient B

Problem: Two friends liked studying about the Earth's atmosphere. Vick studied more about the troposphere, while Frank studied more about the Greenhouse Effect. Which friend studied less about carbon dioxide?

A:
Vick