In chickens, the allele for a pea comb (A) is dominant to the allele for a single comb (a). A mother with the genotype Aa and a father with the genotype Aa produce an offspring. What is the percentage chance that the offspring will have a single comb?

What's the waste product of electrons and pyruvate combining in fermentation?  

The greenhouse effect a. something that has occurred for millions of years b. an unnatural phenomenon caused by humans that maintains earths temperature range. c. the results of the differences in the angle of the suns rays d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere

In the sentence "a mining company will consider the distribution of coal when deciding how to mine the coal," what does the word distribution mean?