Q: Fact 1: Carbon dioxide concentrations in the air have increased over the last decade dramatically. Fact 2: Carbon dioxide is formed by burning carbon. Given the two facts above, burning carbon concentrations have what? | OPTIONS:
- Greenhouse gases
- Chemical energy
- reduced significantly
- increased dramatically
- Plant growth is reduced
- heat energy
- shrunk
- declined spectacularly
A: increased dramatically

Q: Fact 1: An animal requires air for survival. Fact 2: It is breathed in by animals and restored to the air by the photosynthesis mechanism of plants. Given the two facts above, animals rely on what for survival? | OPTIONS:
- proteins
- glycogen
- rocks
- sunlight
- stars
- weeds
- cellulose
- plants
A: plants

Q: Fact 1: Mutations may change the structure of a chromosome or just change a single nucleotide. Fact 2: Mutations are changes in genetic information. Given the two facts above, alterations in genetic information may change a chromosome's structure or one? | OPTIONS:
- nitrogen
- harm them
- Plants growth
- Damages them
- spectrum
- nuclear waste
- nucelotide
- nitrate
A: nucelotide

Q: Fact 1: Planting trees has a positive impact on an ecosystem. Fact 2: Forest ecosystems, from trees to microbes, remove pollutants in a number of ways. Given the two facts above, what can planting trees reduce? | OPTIONS:
- Pollutants
- energy barrier
- competition
- temperature
- Fire danger
- Shade
- Trees
- disease
A: Pollutants