The snowy owl lives in the tundra, a cold biome in north america. in the year 2000, there were 200 snowy owls in a sample of the tundra. in the year 204, there were only 126.
calculate the change in the snowy owl population size

Explanation:

In 2000 there were 200 snowy owls and in 2004 there were 126 snowy owls .

so, the number of snowy owls decreased is : (200-126)

= 74

now this number has decreased in 4 years . so per year decrease is : (74/4)=18.5

18.5

Explanation:

We are given that there were 200 snowy owls at first and then after four years, the population dwindled to 126.

The difference is 200-126, or 74.

There was a gap of 4 years, and it's a constant rate, so our answer is 74/4, or 18.5.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."