The waning of the COVID-19 pandemic is bringing some workers back to offices in a time of rising gasoline prices. Those two factors appear to be attracting more riders to mass transit light rail lines —but not necessarily to buses, streetcars and other modes of public transportation. Fulton Schools Research Professor Steven Polzin, a civil engineer who specializes in transportation, says it’s difficult to ascertain precisely where public transit trends are moving. He expects that many workers won’t return to offices full time and other sources of ridership will be hard to find. He foresees overall mass transportation ridership nationwide increasing in the coming year, but not by more than about 60 percent.