V-shaped valley
As the river erodes downwards the sides of the valley are exposed to freeze-thaw weathering which loosens the rocks (some of which will fall into the river) and steepens the valley sides. The rocks which have fallen into the river help the process of corrasion and this leads to further erosion.
Answer:
I think its C because it releases carbon
The spiders have became resistant to the pesticide.
Answer:
75% brown, 25% white
Explanation:
This question involves a single gene coding for color in chickens. The allele for brown color (B) is dominant over the allele for white color (b).
According to this question, a brown rooter with genotype 'BB' was crossed with a white hen (bb). The offsprings in the F1 generation will all possess the 'Bb' genotype and be brown colored. However, if these F1 offsprings are self-mated i.e Bb × Bb, the proportion of F2 offsprings will be 1BB, 2Bb, 1bb.
Since BB, Bb and Bb offsprings are Brown in color and bb is white in color, this means that the expected phenotypic appearance of the F2 offsprings will be:
¾ or 75% brown and ¼ or 25% white