What problems did Eli Whitney solve by inventing the cotton gin?

How many sheets on a average roll of toilet paper? What effects do years of weathering have on a landscape? How do roped elevators work? How many millimetres squared in a centimeter squared? Do all violins sound the same to the orchestral layman, or do more expensive ones have a better sound quality? Write the name and symbol of a solid element and a liquid element in the same group? What type of energy is torque? Why don't you need to worry about the number of neutrons when calculating the charge of an ion? Which one of the following is a kind of organic sedimentary rock formed from the decayed? Is it true all scientific studies are shared through publications? What methods might be used to enable clients who are deteriorating phisically to feed themselves? Why critical thinking and skepticism are important to scientific inquiry? Diagram completely a cross between homozygous checkered red birds with plain brown birds Summarize the expected F2 results? How to make a science working model? When would you not correct pH even if it was acidic or basic soil? How would you use the word advantage in a sentence? What is the small magnifier used to observe the details on a printed sheet? What is the purpose of controlling an experiment is to? What are the units of measurement from smallest to largest? What does the word occasionally mean?