if there are 250 million people in the United started most of them eating at the tertiary level of consumption, how many people could we feed at the primary level? Use 50% energy lost to each level to calculate

Coat color in cats is determined by genes at several different loci. at one locus on the x chromosome, one allele (x ) encodes black fur and another allele (xo) encodes orange fur. females can be black (x x ), orange (xoxo), or a mixture of orange and black called tortoiseshell (x xo). males are either black (x y) or orange (xoy). bill has a female tortoiseshell cat named patches. one night, patches escapes from bill\'s house, spends the night out, and mates with a stray male. patches later gives birth to the following kittens: one orange male, one black male, two tortoiseshell females, and one orange female. what are the genotypes of patches, the stray male, and the kittens?

Are the earth's ocean floor and continents the same age geologically? why or why not?

What causes darkening of the skin as melanin production increases