The data for the country of Upper Mongoose are given in the table below. All figures are in billions of dollars. Category Net exports Value of new goods and services produced in the underground economy Personal consumption expenditures Value of the services of stay-at-home parents Gross domestic investment Government purchases Total Value $ 50 100 450 50 150 100 $ 900 Instructions: In parta, enter your answer as a whole number. In parts b-c, round your answers to 2 decimal places a. What is Upper Mongoose's GDP for the year? $ billion b. What is the size of the underground economy as a percentage of GDP? percent c. By what percentage would GDP increase if the value of the services of stay-at-home spouses were included in GDP? percent