Answer:
there is no clear explanation why some people become violent while sleepwalking
Explanation:
Sleepwalkers who are suffering from stress, sleep deprivation, and depression do seem more susceptible to experiencing violent episodes than others, but there is no medical proof that negative emotions result in homicidal sleepwalking.
Answer:
A simple microscope
Explanation:
Because it only has a single lens
Genetic drift happens by chance and can make an allele disappear completely from a gene pool, even if it was a desirable trait that should have been passed down to offspring. The random sampling style of genetic drift shrinks the gene pool and therefore alters the frequency the alleles are found in the population.