suppose 10 percent of households earn over 80,000 dollars a year,and 0.25 percent of households earn over 450,000. a random sample of 400 house-holds has been chosen. in this sample, letxbe the number of households thatearn over 80,000, and letybe the number of households that earn over 450,000.use either the normal or the poisson approximation, whichever is appropriate ineither case, to nd the simplest estimates you can for the probabilitiesp(x48)andp(y2)