MISSING STUDENT’S KIN MAKE PLEA VIA BILLBOARD

Family and friends of Kristine Kupka, a pregnant Baruch College student who disappeared two years ago, installed an oversized billboard next to the Brooklyn-Queens Expressway yesterday in a desperate plea for information in the case. "Can you imagine having the person that you love the most out there, and you don’t know what happened?" asked her sister, Kathy Kupka, 35, as she waited for the sign to be unveiled. She huddled with a group of Kristine’s friends.

"It’s unspeakable, the anguish that we feel," she said. Kristine Kupka, an honor student originally from the Midwest , was last heard from on Oct. 24, 1998 . She allegedly left a message on her sister’s answering machine saying she was going to spend the day with Darshanand (Rudy) Persaud, her former boyfriend and the alleged father of her unborn child. She has not been seen since. Kathy Kupka said she hopes the brightly colored, 22-foot vinyl sign, which hangs on the side of a building on N. Eighth St. in Williamsburg , will help flush out information that would help bring closure in the case. "Our hope is that someone who knows something will see this sign and be inspired to come forward," said Kathy Kupka, who has worked tirelessly on her sister’s case for the past two years. "Of course it would be nice if we could get an arrest. But what we really want is to find my sister’s body." Police have said that they suspect foul play in the case, but no one has been charged and the investigation is still open. Kristine Kupka’s family and friends, however, believe Persaud is involved. They say Persaud, who had just married someone else, was unhappy about Kupka’s pregnancy. "To save his family, Rudy ruined my family," said Kathy Kupka yesterday. "That is just not right." Kathy Kupka said the BQE sign - which states "Missing/Murdered" - is also designed to keep attention on the case until it is solved. "I don’t want Kristine to be forgotten," she said, wiping her eyes. "I’m not going to let that happen." Suzanna Riordan, 26, one of Kristine Kupka’s close friends from Baruch, agreed.