Assume a demand equation for good 'x': upper q equals 9 minus 0.1 p minus p subscript y baseline plus 0.01 p subscript z baseline plus 0.0005 upper y; where p = own price of the good py = price of a related good = $3 q = quantity demanded pz = price of a different related good = $200 y = consumer income = $4,000/mo. the quantity demanded as a function of the price can be written: q = nothing if the price of this good 'x' is equal to $42 per unit, what would be the quantity demanded? nothing units. (enter your response rounded to one decimal place)