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Indicate whether the specified alkyl halides will form primarily substitution products, only elimination products, both substitution and elimination products, or no products when they react with sodium methoxide. 1-bromobutane 1-bromo-2-methylpropane 2-bromobutane 2-bromo-2-methylpropane

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?

What produces wave a)sound b) heats c)transfer of energy d)vibrations