<prompt> Translate the following text to EnglishKatika barua kwa Msimamizi Whitman, Seneta Jeffords na Lieberman waliomba uchambuzi wa matukio manne tofauti, wakiomba EPA kuchambua gharama na faida, ikiwa ni pamoja na sekta zote za uchumi na athari kwa pande zote za usambazaji na mahitaji ya usawa, ya matukio yafuatayo ya udhibiti wa uzalishaji wa uchafuzi wa mazingira kwa jenereta za umeme za taifa.  <response>: In the letter to Administrator Whitman, Senators Jeffords and Lieberman asked for an analysis of four different scenarios, requesting that EPA analyze the cost and benefits, including all sectors of the economy and impacts on both the supply and demand side of the equation, of the following multi-pollutant emission control scenarios for the nations electricity generators. 