Also. . .

* Cohr Inc. said Securities and Exchange Commission officials questioned executives about the hospital equipment-servicing and group-purchasing company, including its plans to find a buyer. Earlier in the week, the Chatsworth-based company reported net income for the year to March 31, 1997, of 42 cents a share, less than half the 88 cents it reported in May 1997. The company had warned of the revision in February.

* Pan Am Corp. gave up on resuming scheduled service and won permission from a bankruptcy judge to operate as a charter carrier. The judge also said it was too soon to consider a motion by a federal trustee to halt all Pan Am operations and sell off its assets, something Pan Am’s unsecured creditors did not support.

* Pacific Bell will invest $2 billion in California’s phone network next year, including $500 million in the L.A. area, the company said. The upgrade will include an advanced network for the entertainment industry that can transmit audio and video at super speeds.

* The National Transportation Safety Board extended an investigation into a string of crashes on the Union Pacific railroad to determine the effectiveness of the carrier’s new safety program.

* Litton Industries Inc. elected Michael R. Brown, 57, as chief executive, succeeding John M. Leonis, 64, who remains as Litton’s chairman. Brown retains the title of president of the Woodland Hills-based company.