Which kind of good might not be bought when price rise? complement substituteluxuryinferior good

The market demand curve for a popular teen magazine is given by q = 80 - 10p where p is the magazine price in dollars per issue and q is the weekly magazine circulation in units of 10,000. if the circulation is 400,000 per week at the current price, what is the consumer surplus for a teen reader with maximum willingness to pay of $3 per issue?

According to the video, the gross national product had declined from $104 billion in 1929 to about in 1933.

You are considering the purchase of one of two machines used in your manufacturing plant. machine 1 has a life of two years, costs $20,000 initially, and then $4,000 per year in maintenance costs. machine 2 costs $25,000 initially, has a life of three years, and requires $3,500 in annual maintenance costs. either machine must be replaced at the end of its life with an equivalent machine. using eac which is the better machine for the firm