please answer quickly for a great rating

You are asked to evaluate a proposal to replace a water pump which will produce total benefits of $560,000 over the next five years at a cost of $220,000. The existing pump would produce benefits of $400,000 over the same period and can be sold for $70,000. The net benefit of the proposed new pump is: $340,000 $180,000 $150.000 None of the given answers is correct $160,000