Assume that the free trade unit price of a lamp is $200 and unit cost of an input for a lamp is $100. Given this information about lamp production in a country, calculate the effective rate of protection (ERP) afforded to the lamp industry by a 12% tariff on lamps and each of the following tariffs on lamp in outs.
a) 12% tariff on imported lamp inputs
b) 5% tariff on imported lamp inputs
c) 20% tariff on imported lamp inputs
d) 0% tariff on imported lamp inputs