Suppose Anna likes fireworks.Hermarginal benefit from setting offfireworks isgiven by(Q is number of fireworks):

MB_a=70- Q

She needs to buy the fireworks from Indiana.She needs to drive there and pay for the fireworks.Thus her marginal cost is:

MC_a=10+Q

Bob wants to have a quiet evening after a long day at work.Anna's fireworks generate a marginal cost to him of:

MC_b=10+3Q

What isthe market outcome?In other words,how many fireworks will Anna set off if she only takes her own costs and benefits into account?