DEAR MISS MANNERS: When I am using a one-person public restroom -- the kind with one door that locks -- often someone will try to open the door, and, finding that it is locked, will immediately follow up with knocking. Do you consider this rude?

When I am the person on the outside, and I try the door and find that it is locked, I leave the occupant in peace and wait my turn. I even feel a bit guilty for disturbing them or possibly startling them. I would never dream of further disturbing them by knocking.

I once asked a woman why she knocked after already trying the door, and she told me she was just letting me know that someone was waiting. I believe that trying the door is signal enough that someone is waiting. I interpret the additional knock as an indicator that the person is being pushy and wants me to hurry.

What do you say? Is it rude to knock?

GENTLE READER: By definition, everyone hoping to enter a restroom is in a hurry. Miss Manners would think that anyone inside should have fresh empathy for that state.

You should also understand that while rattling and knocking both make noise, they are different gestures. The rattle, a utilitarian way of determining whether the door is unlocked, is not subject to etiquette classification. A knock, in contrast, is a polite signal to the person inside that there is someone outside.

This need not deprive you of whatever time you need for the primary purpose of a restroom. But if you are in there experimenting with hairstyles, it should suggest that you yield to more pressing needs.

DEAR MISS MANNERS: My significant other and I were invited to a dinner hosted by another couple, with a third couple also in attendance. We were asked to bring dessert, so we brought a large selection of cupcakes.

My SO and I put a lot of effort into picking out flavors for each guest rather than opting for a random assortment, and we were looking forward to doling them out after dinner.

The hosts’ neighbors dropped by unexpectedly before dinner and were asked to stay. I felt slightly annoyed that our deliberate cupcake selection would be thrown off, but it hardly mattered when I realized that the host had already allowed each of his two kids to help themselves to a cupcake.

Was I justified in feeling annoyed by my dessert being distributed not as I’d thoughtfully intended, or was it considered the hosts’ right to do with it what they pleased?

GENTLE READER: Personalized cupcakes?

Miss Manners is loath to discourage thoughtfulness, personalization or cupcakes, but surely that sort of specialized effort is best made when you are the host and can control the circumstances.

Please stop feeling insulted. Once you had agreed to bring dessert, it was not your prerogative to decide when the children could eat or whether the neighbors would be welcomed.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: I work in a fire station amongst people who, 99 percent of the time, could care less about any form of etiquette.

Due to the public’s appreciation of our services and lots of birthdays and social events, the station is a dumping ground for cake. We get at least two a week.

I know that for some reason, everyone else on the planet cuts cake working from the outside toward the inside or center. Where is the rule that states, “Thou shalt begin to consume cake from the outside edge and progressively whittle closer to the interior”?

Every time that we receive a new cake, I always try to be the first person to take a sample. I never cut out squares or pie shapes; I always carve out an oblong shape and always in the MIDDLE of the cake, thus leaving the outer perimeter intact.

Whenever I do this, my co-workers always seem perturbed and act as if the cake is ruined. Without fail, these whining hypocrites will wind up completely consuming the cake.

What’s wrong with them, or what am I missing here?! Mind you, I’m not talking about a thousand-dollar multi-tiered wedding cake. To the contrary, I’m talking about a $15 cheapo from the local grocery store, or something homemade from a person who dropped it off and will not be sharing it with us.

With all of that said, what the hell difference does it make where the chunk of cake came from?

I can’t think of any other food dish where an item is expected to be cut out in a certain way. What makes cake so special? I’m retiring in a year and would love to set this conflict to rest before I go.

GENTLE READER: How on earth do you cut a piece from the middle while keeping the rest intact? And why would you want to?

Is it really worth the effort this must take -- not to mention the resulting frosting on your sleeves -- just to prove a weirdly specific and irksome point to your co-workers? Or more likely, to play a hoax on Miss Manners?

Your co-workers are likely challenging your technique because it is leaving them with a thoroughly touched and mangled cake in your wake. In hopes of your properly enjoying your retirement, however, Miss Manners suggests that you cut a large piece of cake for yourself, big enough for you to create whatever fun shapes you want in it afterwards. Then, please, just leave the rest of it alone.

DEAR MISS MANNERS: I am wondering if it is considered polite to leave a spray can of air freshener in the guest bathroom to be used at the guest’s discretion. If so, where should the can be placed?

I’ve tried placing it on the floor near the toilet, but guests don’t seem to take the hint. What does Miss Manners suggest?

GENTLE READER: That you get better-smelling guests.

Leaving air freshener in an attractive container in plain sight is all that you can reasonably do. If the results are not to your satisfaction, Miss Manners suggests that you discreetly follow up after your guests have left.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: My public, stated reason for leaving my job is that, in addition to an upcoming maternity leave, I will need some time to work on my professional qualifications, including improving my grasp of the local language and dedicating the time and effort necessary to advance.

However, I am also leaving to get away from my boss. His expectations are inconsistent and unclear; he did nothing to improve my working conditions, and his attitude is bad more often than not. Despite this, I expect to receive a good letter of recommendation from him, since I have been a dedicated employee for many years and am sticking to my story about leaving for my own development in all public and professional contexts.

I am working closely with the person hired to replace me. We are sharing an office and will spend almost every workday together until I leave. She has begun picking up on some of the dysfunction in our department and asks pressing questions about it, expressing her frustration with the way things are run.

How diplomatic and/or cautious should I be in addressing her concerns, describing what it has been like working with my boss, etc.? On one hand, I know that it is highly inadvisable and/or rude to bad-mouth one’s boss. On the other hand, we are working together intensively, these are issues she has noticed on her own, and I feel that being too cagey would come off as ridiculous obfuscation.

In addition, there is the real possibility that if she senses I am hiding something but does not know exactly what, she will spin the situation into something even more serious, and perhaps choose not to stay with the company.

Is there a polite way to walk the line between discretion and honesty in this situation?

GENTLE READER: Not, Miss Manners suggests, until the letter of recommendation has been safely written.

Miss Manners is not crass enough to imply that this is the only reason that you should not bad-mouth this gentleman unsolicited, only that it is an added incentive.

Your best course of action would be to continue to allow your colleague to draw her own conclusions. If she finds your boss challenging, you may delicately concur or offer solutions that have previously worked for you. If it gets to the point where she asks you directly whether or not he is truly awful, however, you should demur, telling her to talk directly to him or other current co-workers.

This is not only good form, but highly practical. Those who are staying on have likely found better ways of managing this difficult boss.

DEAR MISS MANNERS: A friend of mind sometimes has involuntary flatulence. I wonder what is the proper way to deal with this in public.

GENTLE READER: What did you have in mind? “Whoa! That was a good one”? Miss Manners suggests that you ignore it, vehemently resisting the urge to laugh or look disgusted. She will further refrain from pointing out that you probably already knew that.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)