Problem: Hydrologists studied two samples of rain water. Jim studied an acid rain sample from a nearby city, and Dan studied a sample of water from another town. Which hydrologist didn't learn that acid rain falls in freshwater habitats?

A: Dan

Problem: John an Keith are coworkers in a chemistry lab. Yesterday, they conducted there tests, test A, test B, and test C. In test A, John kept a substance in solid state, but Keith changed the same substance from solid to liquid state. In test B, John conducted a chemical reaction in low temperature, but Keith conducted the same chemical reaction in high temperature. Finally, in test C, John kept an unstable material in room temperature, but Keith kept the same unstable material in a cool container. In test A, whose substance would have higher temperature, John or Keith?

A: Keith

Problem: Two regions of the same country had very different climates because of the different landscapes. East region had an alpine landscape, was situated in the mountains. North region was flat and located at sea level. Which region didn't have a colder climate?

A: North

Problem: Frank and Noah were two researchers. Noah researched the climate of Antarctica, while Frank researched the climate changes of Madagascar and the Southern tip of Africa. Which researcher observed a particularly strong warming?

A:
Noah