b-1. Compute the balance on the U.S. primary income. b-2. What does the balance on the U.S. primary income you computed above mean? c-1. Compute the balance on the U.S. secondary income. c-2. What does the balance on the U.S. secondary income you computed above mean? d-1. Compute the balance on the U.S. current account d-2. What does the balance on the U.S. current account you computed above mean? Complete this question by entering your answers in the tabs below. Compute the balance on the U.S. primary income. Note: Negative amounts should be indicated by a minus sign. Round your answer to 1 decimal places. Enter your answers in billions of dollars (e.g. $4,000,000,000 would be entered as $4 )