Sometimes PCR fails and instead of having two bands you end up with just one. The elephants represented in lanes 3 and 5 could have been a match to the ivory sample if you failed to amplify one allele in either the ivory or the sample, so you cannot exclude these choices without running the experiment multiple times. On the other hand, you can definitely eliminate the elephants in lanes 1, 2, 4, and 6. Explain why.

answer; the correct answer is (beta)

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus

a physical change is being made.

the correct answer is - d. china has a large and growing population.

the fact that china has a large (the biggest) population, and it is still growing, doesn't hinder the agriculture production in the country. in fact, it can for increased production in the agriculture, since there's more labor force, as well the sheer mass of people produces lots of scientists that come up with new inventions as to how to improve this sector. nice example is the inner mongolia region in china, in general dominated by the gobi desert, but few scientist came up with a nice idea as to how to make the region productive by using plants that are very resistant to droughts, so lots of people have been employed, and the region is becoming greener and greener each year, and the production of food in this region is also increasing.