Today, we put on the Answer Man hat and take three readers out of their misery.

"A few days ago," writes Col. L.J. Fishkin of Southwest, "I was barely listening to music from a completely obscure and rarely-if-ever performed opera-ballet entitled 'Mlada,' composed by Rimsky-Korsakov almost a century ago."

One regal, almost stately, passage suddenly sounded familiar. Col. Fishkin recognized it as the theme music for the weekly Martin Agronsky talk show. "Are you as curious as I am," he asks, "who attached this music to the program, and why?"

The who, Colonel, is Buddy Belote, studio technician and sound man for the Agronsky show. (If the surname is familiar, it ought to be. Buddy is the father of Melissa, gold medal-winning swimmer in the 1972 Olympics). Belote Pere is a symphonic musician on the side, and 'Mlada' has long been one of his favorites.

The why? "We just liked it," said producer Rich Adams. "We wanted something that was fairly serious and didn't sound too razzle-dazzle . . . Buddy has a good sense of music, and shared it with us."

From the TV studio to the grocery store, and a question from Tim Resch of Alexandria.

I don't suppose you've lost much sleep wondering where prune juice comes from, but Tim has -- at least since the day he wandered into a Grand Union supermarket and read the label on a bottle of the house brand.

"Unsweetened Prune Juice," it said. "A Water Extract of Dried Prunes."

Tim was confused. "I always thought prunes were dried plums," he writes. Why dry a dried fruit further in order to produce something wet?

According to Robert Mohel, corporate vice president for product development and quality control at Grand Union, the answer lies in the process by which one does, and doesn't, obtain prune juice.

The juice is not produced by a giant machine that squeezes each prune like a defensive tackle. It is obtained by dunking super-dried prunes in water and heating the mixture.

Under these conditions, says Mohel, the prunes suck up the water, then decompose into those little floating, fruity tidbits you find in the bottle at the store. At the same time, the liquid takes on the purple-brownish color that we all know and (perhaps) love.

Obviously, the process is easier if the prune you start with is as absorbent as possible. That's why super-dried prunes are used -- they start with less liquid in them, so they can absorb more.

Finally, an old bugaboo hereabouts, but one which has surfaced again recently in this transient burg of ours.

S.K. of McLean asks: Why isn't there a J Street in Washington?

Afraid your eyes are too firmly rooted on downtown, S.K. Out in Far Northeast, there's a Jay Street -- although it's named for John Jay, the noted American diplomat and lawyer, and not for the 10th letter of the alphabet.

The real reason there's a "skip" in the "letter streets" is ambiguous penmanship. According to Elizabeth Miller of the Columbia Historical Society, "in the script of the 18th Century, I's and J's are almost exact duplicates. In order to avoid confusion, they just did not use the letter 'j.' "

Miller says she's particularly anxious to lay to rest the notion that the city fathers wanted to slight John Jay in the city's other quadrants of Northwest, Southwest and Southeast.

You historians will recall that Jay wasn't exactly the most popular diplomat of the post-Revolutionary War period. He negotiated a treaty with Great Britain that many American politicians of the time, President George Washington among them, thought was far too generous to the other side. Miller says, however, that there is "no evidence that the city planners and other government officials omitted 'J' because they were having troubles with John Jay."

A far tougher question: why is there no X Street, Y Street or Z Street in any quadrant of Our Fair City? Answer in a few days.