Why are these moths called peppered moths

From which layer of atmosphere is the top layer of the thermosphere? a. troposphere b. stratosphere c. mesosphere d. exosphere hurry me i will give a braineilst

Which gas found in the earth's atmosphere greatly impacts the daily range of temperature on earth. a) oxygen b) hydrogen c) nitrogen d) water vapor

Which best describes a gene? a. a sister chromatid b. a chromosome c. a tetrad d. a piece of a chromosome