Subsidy costs, new equilibrium with the demand curve, economics graph homework help

Graph of straight-line supply and demand curves that intersect at (800, $40). The supply curve has y-intercept at $120 and x-intercept at 1200. The demand curve has y-intercept at 0 (the origin). If you shift the supply curve up vertically by $30 the new equilibrium with the demand curve would occur at (600, $60)” 

I like this old school graph… look at it carefully. A $30 per unit production subsidy would cost how much to taxpayers?

Thanks for installing the Bottom of every post plugin by Corey Salzano. Contact me if you need custom WordPress plugins or website design.