The movement of water across a membrane.
The answer is; D
Solar cells usually convert solar energy into electricity which could later be reserved. The efficiency of solar cells is still low, compared to other sources, with a conversion rate of 15% - 22%. This reduces the attractiveness of solar cells as a competitive source of energy. This also makes this form of energy expensive due to its inefficiency.
<span>Modern humans have been around for a very short period of time. There are differences in race, asian people tend to be smaller, stuff like that. The problem is different races marry and those genes mix. If Asians only married pure blood Asians, Africans only married and procreated with other Africans thanks in hundreds of thousands of years different sub species would most likely start to occur. Seeing as how human population is all connected today, that won't happen.</span>
