An employee hiring sign is seen in a window of a business in Arlington, Virginia, April 7, 2023.Elizabeth Frantz | ReutersThis is CNBC's Morning Squawk newsletter. Subscribe here to receive future editions in your inbox.Here are five key things investors need to know to start the trading day:1. Economics 101Investors and economic policymakers alike are counting down to this morning's delayed nonfarm payroll report, due out at 8:30 a.m. ET. The data comes less than a week after the Federal Reserve cut intere ...