Problem: the students used yeasts in two different experiments: they baked bread using baker's yeast, and made beer, using brewer's yeast. They learned a lot about sugars and chemistry. Which yeast is worse for alcoholic fermentation?

A: baker's yeast

Problem: The southern province was exposed to intensive grazing for many years , and now soil quality is poor and dust storms are present. The northern province has more fertile soil, more trees. Which province experiences more soil erosion?

A: southern

Problem: Bobby and Sally are siblings that currently live in different cities. Bobby lives in a city that has wildfires on a regular basis. The local government is effective at combating these fires, but there are still quite a few over the course of a year. Sally lives somewhere that has never had a wildfire before, and she wasn't even aware they existed until her brother started talking about them. Who will experience a sore throat more often?

A: Bobby

Problem: Two friends read about respiratory systems. Paul read more about the lungs of mammals, while Pete read more about the lungs of frogs. Which student read less about human lungs?

A:
Pete