How many pairs of chromosomes does a healthy human have?
A healthy human will have 23 pairs, so 46 total. Depending on gender, the human will have either two X chromosomes for female, or an X and a Y for a male.
What happens to the supply and demand curves for pepsi when the price of coke goes up?
The price of coke going up lowers the demand for coke. Since these two goods are substitutes, people will move towards pepsi. The demand for pepsi will go up, increasing the price and the quantity demanded.
If x^2 + y^2 =400 , and y=12, what is x?
y^2=12^2=144. This means x^2 +144=400, and that x^2=256. Finally, x=16.