During a total solar eclipse, the earth, sun, and moon are arranged in a line, and light from the sun is blocked out of view for a certain part of the earth by the moon. in what order do the earth, sun, and moon line up? a. earth, moon, sun b. sun, earth, moon c. earth, sun, moon d. moon, sun, earth

During a total solar eclipse the moon is lined up between the sun and the moon, blocking the sunlight. The answer is A.

"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."

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.