WASHINGTON — U.S. employers added a robust 235,000 jobs in February and raised pay at a healthy pace, making it all but certain that the Federal Reserve will raise short-term interest rates next week.Friday’s jobs report from the government made clear that the economy remains on solid footing nearly eight years after the Great Recession ended.The unemployment rate dipped to a low 4.7 percent from 4.8 percent, the Labor Department said. More people began looking for jobs in February, a sign of confidence that raised the proportion of Americans working or seeking work to the highest level in nearly a year.The gains in hiring and pay, along with higher consumer and business confidence since the November election, could lift spending and investment in coming months and accelerate economic growth. Americans are buying homes at a solid pace, and manufacturing is rebounding, in part because of improving economies overseas.Investors responded initially by sending stock prices up sharply Friday. By late morning, though, stock indexes were up only slightly.The February jobs data likely provides the final piece of evidence the Fed needs to feel confident enough to raise rates next week for the third time in 15 months. The Fed’s inclination to tighten borrowing rates reflects how far the economy has come since the central bank cut its benchmark short-term rate to zero in 2008 and kept it there for seven years to support a fragile economy.