*Question*: Why do scientists perform multiple trials of the same experiment? OPTIONS:
- to include additional variables in the experiment
- to complete the steps of the experiment in less time
- to find a less expensive way to conduct the experiment
- to increase the likelihood of accurate experiment results
*Answer*: to increase the likelihood of accurate experiment results

*Question*: Different species of carnivorous animals that share the same habitat in an ecosystem may OPTIONS:
- become decomposers
- compete for food
- produce their own food
- mate with each other
*Answer*: compete for food

*Question*: Solar radiation is a combination of light with different wavelengths. Which type of ray can harm human skin the most? OPTIONS:
- infrared
- microwave
- ultraviolet
- visible
*Answer*:
ultraviolet