Moody’s Investors Service placed Atlantic Richfield’s long-term...

Moody’s Investors Service placed Atlantic Richfield’s long-term debt and commercial paper ratings under review for possible downgrading, saying lower oil prices may affect the company’s financial flexibility . . . Unocal said it will temporarily close its molybdenum mine and mill in Quedstra, N.M., and its roasting plant in Washington, Pa., due to a decline in product prices. The action will result in about 600 layoffs . . . In its third auction this week, the Treasury Department sold $7 billion in 30-year bonds at 9.28%, down from 9.93% at the last auction in November. The rate was the lowest since 30-year bonds sold for 8.91% at an auction on Aug. 2, 1979 . . . Distillers Co. of Britain rejected a new takeover offer from Argyll Group, which raised its bid to 2.343 billion pounds from 1.864 billion pounds . . . IBM said it would join 20 other companies as a founding member of the Corporation for Open Systems, which will attempt to create a set of standards for communications between computers . . . The merger of Lorimar and Telepictures was approved by shareholders; the stock-swap deal, valued at about $300 million when it was tentatively agreed to in October, is now worth about $405 million because of a 30% increase in the price of Telepictures stock . . . Litton Industries said it has completed the sale of its Itek Graphic Systems division to a group of private investors . . . The Dutch government agreed in principle to cut its 55% holding in the Dutch national airline KLM to a minority stake, according to KLM and the Dutch Transport Ministry . . . Occidental Petroleum extended to Feb. 14 the expiration date and proration period for its tender offer for Midcon stock and said the waiting period under the Hart-Scott-Rodino Act will end on the same date.