What was going on when I was born?

President Carter, campaigning here with Senator Edward M. Kennedy, announced last night that he would seek to ease the "crushing burden" of welfare and Medicaid costs in New York City.

Thousands of subway riders met delays yesterday morning because of a heavy smoke fire and a teen-ager's fall onto a subway track in Manhattan. Thousands more were delayed because, on three troubled D trains in Brooklyn, frustrated passengers refused to leave.

Ronald Reagan's efforts to capture New York's 41 electoral votes, a tantalizing prize that would almost guarantee him the White House, are being hindered by doubts within his own party and countered by President Carter's all-out attempt to lock in traditional Democrats, especially in New York City.

Representative Elizabeth Holtzman is appealing to a broad geographic, ideological, political and religious spectrum in the contest for United States Senator from New York, a New York Times/CBS News survey showed yesterday.

UPTON, L.I. THEY called it Inner Mongolia. It was a stark and almost inaccessible workplace that James Cronin and Val Fitch discovered for themselves in a crowded Brookhaven National Laboratory here in 1963. But it was big enough to enable the pair to conduct experiments that won them the Nobel Prize in Physics last week.

WASHINGTON, Oct. 20--The Food and Drug Administration proposed mandatory labels on tampon packages today to warn women of the danger of toxic shock syndrome.

SAN FRANCISCO, Oct. 20--As recently as last year, the Natomas Company was thought of mainly as a holding company for American President Lines. The skyrocketing price of oil has changed all that.

IN the not-too-distant future, some experts in aging now believe, there will be few deaths in youth or middle age and most of the elderly will have vigorous good health almost to the end, at age 85, give or take a few years.

CHICAGO, Oct. 20--A few months ago, in a talk to securities analysts, Richard J. Ferris, the chairman of United Airlines, drew frequent comparisons between his company and Delta Air Lines, the industry's most profitable airline. He boasted repeatedly that United, the nation's largest carrier, had met its goal of becoming No. 3 in several categories that measure airline performance.

WARSAW, Oct. 20--It is probably an exaggeration to say that any Pole stands to lose his Polish citizenship if he cannot hum the entire "Polonaise Fantaisie" or explain why Chopin ended his love affair with George Sand or lead you through the streets of Warsaw to the exact spot in the pillar of Holy Cross Church where the composer's heart is buried.

Thundering through Central Park at dawn or circling Washington Square, thousands of runners are preparing for the New York City Marathon on Sunday.