DEAR ABBY: I am 8 years old, and I love science. I am writing you because when I go to the doughnut shop, they always give me paper bags when I order my doughnut to eat there. I also notice other people getting bags they don't need because they are eating their doughnuts there, too.

How many trees have to die for no reason?

I care about recycling and how long it takes for things to break down in the earth. What can I do so the doughnut shop will stop wasting bags? -- MANDI IN SCARSDALE, N.Y.

DEAR MANDI: I respect the fact that you are conscientious about how your actions -- and the actions of the people around you -- affect the environment. You are a sharp young lady.

What you should do is speak to the manager of the doughnut shop. Tell him or her that these days a strong selling point in many businesses is that they are "going green." In the case of the doughnut shop, it would cost them less and even gain them more customers if they would stop handing out bags to customers who are eating their doughnuts on the premises and tell them why. (A piece of waxed paper would suffice and create less waste.)

Readers, if you are interested in how long it takes the items we toss into our landfills to decompose, I found the following illuminating. Read on:

Paper ................... 2 to 5 months

Orange peels ............ 6 months

Milk cartons ............ 5 years

Filter-tip cigarettes ... 10 to 12 years

Plastic bags ............ 10 to 20 years

Leather shoes ........... 24 to 40 years

Plastic containers ...... 50 to 80 years

Disposable diapers ...... 75 years

Tin cans ................ 100 years

Aluminum cans ........... 200 to 500 years

Styrofoam ............... Never

DEAR ABBY: I'm having a problem with my next door neighbors. We just purchased a wonderful historical home located in an awesome neighborhood. My problem is, after we moved in, we realized that these people are exhibitionists. They have no window coverings in their home, which has large windows on all sides. At night you can see all the way through to the other side.

Our home has no back door, so when we need to let our dog out, we must walk along the driveway. We refer to it as "walking the gauntlet." This couple eats their breakfast at a table next to the side window dressed only in their night clothes. At 7 a.m., I am in my robe. Should I wave or hang my head in shame?

I know I should have checked the neighbors out before we bought. I come from a rural area, but still, I had blinds. Flaunting my nightwear or my husband's is kind of personal. Please advise. -- PUT OFF IN TEXAS

DEAR PUT OFF: There is nothing shameful or exhibitionistic about wearing one's pajamas to the breakfast table. If the sight of your neighbors' nightwear embarrasses you, plant a lovely, lush, fast-growing hedge between your driveway and their kitchen.

DEAR ABBY: Five years ago, my brother-in-law sent my sister "Rita" and me on an all-expense-paid weekend trip to Canada. He asked me to tell Rita that I had "won" it for outstanding performance at my job and wanted her to accompany me.

To make a long story short, it turned out he did it in order to cheat on my sister. Because we had problems with the arrangements he had made, Rita and I had to return a day early. When she opened her front door and walked in, she caught her husband red-handed.

Ever since that unfortunate incident, Rita has cut off our entire family. She acts as though WE cheated on her, and remains married to this despicable man even though he lives with the other woman.

I don't understand why my sister has pushed away all of the people who love her while maintaining a relationship with a man who cheats on her. I don't know what to do. Any advice? -- MISSING MY SISTER

DEAR MISSING: Your sister may feel that she deserves the treatment she's getting from her husband, or is still hoping that her wandering spouse will return. Because you were part of the deception, she has displaced the anger she should be aiming at her husband and has directed it at you because it is "safer."

Until she finds the strength and courage to accept that her marriage is over, her behavior will probably continue. I'm advising you to go on with your life until she is ready to change hers.

DEAR ABBY: Most of my extended family are pleasant and enjoy each other's company when we meet at family gatherings several times a year. But three of them (all from the same side of the family) are just plain rude. Every event becomes an uncomfortable exercise in bracing oneself for the verbal attacks that come from these critical, judgmental people.

We have tried talking about it, but hear the same refrains -- "I'm not changing," "Accept me as I am," and, "You have no choice but to put up with me because we are family!"

I am a younger member of this family who occasionally spends holidays with friends or traveling. When I do, I am severely chastised by these three relatives, who say I have "no right" to skip family gatherings. If they were nicer people, I would want to spend more time with them.

I want to do the right thing, but what do people who have the same ancestry "owe" each other when there is no connection of friendship or goodwill? -- RELATED IN NAME ONLY IN SAN JOSE, CALIF.

DEAR RELATED: I know of no rule of etiquette that states you are compelled to attend every family event. Good manners dictate that you treat those around you courteously. But that does not mean that you must engage in anything more than casual, superficial chit-chat with those who are critical, judgmental and rude.

Because these get-togethers involve extended family, spend the majority of your time with the relatives who make you feel welcome, supported and loved.

P.S. One thing you do NOT owe these folks is an explanation regarding your absence when you choose to avoid them.

DEAR ABBY: I am trying hard to rebuild my marriage. My husband and I have three young children. Four months ago, I met a man (I'll call him "Jack") who made me feel like I haven't felt in a long time. We have not slept together. We tried several times to stop seeing each other, but unfortunately, my attraction to him was too strong.

This week my husband and I separated. I saw Jack this morning. Before things went too far I told him that I had herpes. Abby, he practically had a heart attack -- and ended it on the spot!

The thing is, what I said wasn't true. I just could not think of another way to make him stop being available so I could concentrate on my marriage. I feel like such a coward, and I am heartbroken. Not only do I miss Jack terribly, I also can't bear the thought that someone who made me feel so happy would just turn his back on me.

Would there be any point in telling him that I lied, or did I do the right -- albeit cowardly -- thing? -- WAVERING IN THE SOUTH

DEAR WAVERING: I can see absolutely nothing positive to be gained by approaching Jack again. While I would never recommend lying, yours exposed the man's truth. If he truly cared about you, he would have stuck by you instead of heading for the exit. Consider yourself lucky to have learned the truth while there was still time to save your marriage.

DEAR ABBY: I am concerned about my younger brother. I'll call him "Freddy." Freddy is 18 and very lazy. His girlfriend lives with him at my mother's house.

Our mom is always cleaning their room. She does all the cooking and sometimes even launders their clothes. Mom tells me everything, and she's bothered by this. I live with her, too, but I do my share. I pay half the rent.

How can we let them know we are not their housekeepers, but in a nice way? -- TOUCHY SUBJECT, LAS VEGAS, N.M.

DEAR TOUCHY SUBJECT: I, too, am concerned about your brother. It is time your mother realized that by allowing this arrangement, she has done her son no favors.

The girlfriend should not be living in his room rent-free. (Where the heck are her parents?) If she is a student, she should have a part-time job and contribute something -- and so should Freddy. If he is old enough to have a live-in companion, he should be mature enough to clean up and do a load of laundry.

Your mother should convene a "family council" meeting and start assigning chores. Until and unless she becomes assertive enough to draw the line, she will continue to be taken advantage of. It's not about being mean or nasty. It's about encouraging Freddy to grow up and lessen his dependence upon her.

DEAR ABBY: I am asking this question in all seriousness. While I am using a restroom in a public place, I'm not sure how to respond when someone knocks on the door to see if anyone is there. What's the appropriate answer? -- GOTTA GO IN WALDORF, MD.

DEAR GOTTA: The correct response is, "Occupied!"