Why do national income accountants compare the market value of the total outputs in various years rather than actual physical volumes of production? What problem is posed by any comparison over time of the market values of various total outputs? How is this problem resolved?

An increase in the market price of men's haircuts, from $16 per haircut to $26 per haircut, initially causes a local barbershop to have its employees work overtime to increase the number of daily haircuts provided from 20 to 25. when the $26 market price remains unchanged for several weeks and all other things remain equal as well, the barbershop hires additional employees and provides 40 haircuts per day. what is the short-run price elasticity of supply? nothing (your answer should have two decimal places.) what is the long-run price elasticity of supply? nothing (your answer should have two decimal places.)