the demand function for your brand x shirts is estimated as qd x = 1,000 - 5 px - 10 py + 9 pz+ 0 .001 i the price of x is $ 10, y is $ 4, z is $ 10 and incomes are $ 20,000. 1) what are your sales? ______________ 2) what is the elasticity of demand for x? _______________ 3) what is the cross elasticity between x and z? ______________ 4) are x and z substitutes or complements? ______________ 5) what is the income elasticity for x? ______________ 6) if incomes increased by $ 5,000, what would be the increase in sales of x