NEW YORK, Sept. 20 (AP)ÛÓWall Street received the tonic that it needed todayÛÓ an agreement between General Motors and the United Auto Workers UnionÛÓand the stpek market pulled out of a decline and moved sharply higher.</br></br>' Volume was light, however, dwindling to 2.7 million shares from 3.26 million yesterday, the smallest since July 24 when 2.49 million shares wereÛ÷ traded. Trading was dampened by Yom Kippur.</br></br>Sentiment had the added support of overnight news that the nation's output of goods and services is running at a record level. The market, however, was sluggish in moving to the upside after two straight sessions of sharp decline. Early prices Showed a lower trend. A substantial gain by duPont helped boost the average slightly by noon but the pattern did not become decisively higher unitl news of a labor settlement came from Detroit. Prices advanced on balance thereafter but with little real enthusiasm.</br></br>Dupont was up 4% as it responded to news that the House had adopted a bill which would give duPont shareholders tax relief when the chemical firmÛªs vast hold-</br></br>The Dow Jones industrial average recovered 4.78 at 707.32. The AP 60-stock average rose 1.60 to 252.40 with industrials up 2.20, rails up 1.60 and utilities up .40.