Explain the OBPS and relate it to the emissions Tax system . For example, you might begin by outlining the textbook-type emissions tax system and then use it to illustrate that the OBPS is just a modification of that system. (Hint: the alternative ambient tax system for nonpoint source pollution used a similar modification.) Your explanation should include the use of diagrams(welfare graphs) or mathematics to support your explanation. This part should also explain why the OBPS is used for EITE sectors of the economy and, therefore, why it is part of one of the two policy options to be considered for the upstream oil and gas sector. draw graph on a piece of paper ?