"Consider an economy in which there is 10 households with income tabulated as follows H1. $10,000 H2. $20,000 H3. $25,000 H4. $30,000 H5. $50,000 H6. $50,000 H7. $60,000 H8. $75,000 H9. $90,000 H10. $100,000 a. What is the mean income? Median? Top decile? Bottom decile? b. What s the general pattern of the US income distribution over the last century? How about the timing of the changes?"