An Olympic swimming pool is 50 meters long. You swim from one end to the other four times How many kilometers do you swim?

Which of the following statements is false regarding aromaticity? a. the compound must be cyclic b. the compound must be fully conjugated c. the compound must be planar d. the number of electrons in the pi system must satisfy the hückel 4n+2 rule e. the compound must have a neutral charge

Darla claims that the first periodic table developed by mendeleev was not completely accurate, so it is not useful at all. harmony argues that it establish the periodic table we use today, making it more credible. who is correct and why? darla is correct, because a model that has any mistakes should be thrown out. darla is correct, because a good model would not need to change. harmony is correct, because mendeleev’s model had all of the information correct in the first version. harmony is correct, because mendeleev’s model made predictions that came true.

What layer of the atmosphere is directly above the troposphere?