Nope. In the boat, the anchor displaces its weight of water, but on the lake bottom, it only displaces its volume of water, which is less. The lake level will fall.

Correct!

The answer to the first one is: It flushes.

That is ONE reason. And it's the #1 that was published in the article about the questions asked in a Microsoft interview, from about 1990 or 1995 I think.
What are the other reasons it's round?

Because the fitting mounted in the concrete/asphalt is round.:)

I cheated - wikipedia
 

Circular shape

The question of why manhole covers are typically round, at least in the U.S., was made famous by Microsoft when they began asking it as a job-interview question.[6][7][8] Originally meant as a psychological assessment of how one approaches a question with more than one correct answer, the problem has produced a number of alternate explanations, from the pragmatic ("Manhole covers are round because manholes are round.")[6] to the philosophical.
Reasons for the shape include:

• A round manhole cover cannot fall through its circular opening, whereas a square manhole cover may fall in if it were inserted diagonally in the hole. (A Reuleaux triangle or other curve of constant width would also serve this purpose, but round covers are much easier to manufacture. The existence of a "lip" holding up the lid means that the underlying hole is smaller than the cover, so that other shapes might suffice.)
• Round tubes are the strongest and most material-efficient shape against the compression of the earth around them, and so it is natural that the cover of a round tube assume a circular shape.
• Similarly, it is easier to dig a circular hole and thus the cover is also circular.
• The bearing surfaces of manhole frames and covers are machined to assure flatness and prevent them from becoming dislodged by traffic. Round castings are much easier to machine using a lathe.
• Circular covers do not need to be rotated to align them when covering a circular manhole.
• Human beings have a roughly circular cross-section.
• A round manhole cover can be more easily moved by being rolled.
• If a cover had corners and were bent that would create a protruding point that could puncture tires.
• Most manhole covers are made by a few large companies. A different shape would have to be custom made.

Other manhole shapes can be found, usually squares or rectangles. Nashua, New Hampshire may be unique in the U.S. for having triangular manhole covers that point in the direction of the underlying flow. The city is phasing out the triangles, which were made by a local foundry, because they are not large enough to meet modern safety standards, and larger triangles cannot be found.[9]

I think if someone asked me a question like this at an interview I would tell them they failed psych screening for my prospective employers, but thanks for your time and I will be on my way. These people need to realize that job interviews cut both ways and form a lasting impression of them with persons who are likely to remain in the industry for decades. I have had a few interviews over the years where I doubt the interviewers realized how much harm they had done to their image through their behavior. But I digress. Maybe as applicants we should get smart and bring the same psycho-babble to an interview.

Here is one I asked a great Captain at Alaska, whereupon he just stared at me. Silly boy.

Caveat: not an original question.

Will an airplane weigh less if half the people on it go to the lavatory and pee?

;)

I agree with you, Cubdriver, in the answer I will give to an employer stupid enough to ask me such stupid questions.

Whether the question is stupid or not depends upon two things.
One, what is the position being applied for?
Two, what is the purpose of the question?

For example, if the position being applied for is one that requires immagination and creativity, and the purpose of the question is to investigate the persons ability to develop a creative answer to an absurd question, then asking how a pencil gets itself out of a blender is not a stupid question.

However, if the position being applied for is one that consists of repetative labor, such as working on a production line, then the question is stupid.

In the situation we're most likely talking about - a pilot - then there is a part of the job which does require a level of imagination and creativity, after the checklist is exhausted and there's no solution, what do you do. However in this case, it's probably better to ask a question that's along those lines "Mr. X, assuming you've exhausted the checklist and still can't get the gear down, what do you do?"

The origin of the manhole cover question, for example, came from Microsoft, and even though I have no love of Microsoft, I understand the purpose of the question completely, however I think that a candidate should be informed of the purpose of the question, so that they "talk out" their thinking process. There are some jobs, and being a computer programmer is one of them, where the problem today is completely different than the problem yesterday, so companies want to know "how" a person thinks, rather than "what" they think.

On the old 727, the sink dumped overboard thru a heated drain mast. So, if they peed in the sink, then yes the airplane weight would be less.

Joe

My thoughts on this run along two lines. They are:

1. These kinds of questions are junk science as far as I can tell. If they want to use junk science to eliminate job applicants there are easier and better methods (draw straws, good looks, nepotism, etc.) They aren't going to learn anything from poorly-administered pseudo psychology. The way the OP gave the scenario the "bizarre" questions one might encounter would be given by people who are not psychologists in an environment that is not controlled according to scientific method which is what the typical face to face job interview is. If the testing was supported by rigorous, proven science that would be another thing. I know of such testing and have no issue with it if it is really helpful.

2. I am generally opposed to any company using industrial psychology to control me. Having a company getting inside the head of its employees smacks of invasion of personal rights. It is the same argument that gets going in other areas of public life, such as how much does the NSA (National Security Agency) need to know about the average citizen in order to keep a grip in terrorism? Do they need to know every thought, read every text, read every email, and put every curious event on a watchlist? Should they be allowed to implant RFID tags in anyone they happen to suspect? You get my point, it is a serious and debatable question of personal rights versus the public interest, or in this case the company interest. A person has rights and the inside of their own head should be somewhat private. As soon as I see an industrial psych tests coming my way I generally run for my rights and I urge others to as well.