It is a contract entered into (before marriage) between spouses that dictates the division of the couple's property in the event they divorce.

There are also "post-nuptial" agreements which are the same thing but signed after the wedding, while the individuals are married.

A prenuptial agreement is a contract that declares how each spouse's present and future assets are divided should the marriage end. It is a way for people to protect their wealth against future claims due to divorce.

It's founded on trust. A journalist takes care to report with integrity. So when they receive important information from someone who requests anonymity, a good journalist works to corroborate this information with other facts. Background will only speak to a journalist who they trust will honour their desire for anonymity. Good editors will only publish a story that cites background sources if they trust that the journalist did the work to verify that the facts are at least plausible.

Airplane engines require air to work, that is conspicuously lacking in space. A rocket plane could go to space.

Engines propel by moving molecules from the front of the craft to the back of the craft, hence using a turbofan (move air from front to back with a fan powered by a turbine) or a rocket (blow a mixture of hydrogen and oxygen from the front of the craft out the rear) - a rocket can work in space because I am not relying on atmospheric mass (the air molecules) for propulsion. In space, gas molecules are too far apart for this to work.

The term for this is 'reaction mass' or 'where do I get stuff to toss behind me to make me go forward?'

If someone who is being interviewed wants to help the journalist uncover the truth about a subject but does not want to risk their job or reputation they might tell the journalist something in confidence. They do this by telling the journalist to keep this off their records of what was said in the interview. The journalist would have to abandon their own morals and integrity to tell someone where they got the information from, which might cause them to lose their job. And even then the source will probably deny that they said it. So it is hard for the journalist to print the information as they are not able to verify to others where they got the information from. So it is not as valuable as if the source was willing to go on the record. However it can help the journalist ask the right question and dig in the right places to uncover the truth through other means.

An airplane engine is basically a giant fan that pushes a huge amount of air backwards, which pushes the plane forward and upward.

As you go higher, the air gets thinner and thinner. As you go toward space, airplane engines lose power as they have less and less air to push. (And if you have a jet engine like most modern passenger aircraft, it needs a certain minimum amount of airflow to run at all.)

Ahh yes. I was thrown by OPs comment about the fuel tanks…

… Three main reasons haha

The key reason you're missing is that planes generate lift by moving through the air. As they fly higher, the air is thinner, and thus produces less lift. Planes would eventually reach an altitude where they can no longer climb because they can no longer generate enough lift to climb any higher.

Someone who would like to talk to a journalist to provide information without being identified can ask to speak to the journalist "off the record." If the journalist agrees that the source is off the record, the journalist would use the information without naming the source. This is common where the source would face consequences for being quoted -- e.g., the source wants to give information about their employer without getting fired. This is an agreement between the source and the journalist, which means that the journalist must agree to anonymity up front and the source cannot insist on it afterward (e.g. because they realize they said something that can get them in trouble). Journalists generally follow these agreements because it would be harmful to their reputation and ability to get sources in the future if they were known to burn their sources, but there's likely no other recourse for a source that believe that they were "off the record" and where then cited by the journalist.

There are various types of "off the record" that are understood to exist, and people, especially in politics or national security would generally be familiar with them. The most common are "background" and "deep background," with "background" indicating that the source could only be cited with consent (i.e. the journalist can't say "My sources in the White House tell me..." unless the source agrees) and "deep background" meaning that the journalist can use the information but they can't even anonymously cite the source (i.e. no "My anonymous source at the Pentagon tells me...").

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Airplane wings need to have air around them in order to generate lift. The air which passes over the wing moves faster and at a lower pressure than the air which passes below the wing.

Airplane engines are designed to pull or push the airplane through air. If the air is too thin, or if there is no air, then the engine has nothing to push against.

Two main reasons:

(i) to get to space you need to escape earths gravity completely which requires much more energy than just flying above the surface as regular planes do. You need a shed load more fuel and so need big fuel tanks; and

(ii) travelling through Earths atmosphere is crazy destructive (that’s why things burn up coming back down to earth) so you need special design to withstand the heat.

TLDR: planes don’t go very high compared to rockets.

The clue's in the name: airplanes need air for lift and to run their engines. There is no air in space.

Rockets don't need air, they get their lift from their rocket engines which carry their own fuel-oxygen mixture.

>30,000 people die in cars every year, but no crash helmets for drivers?

That is really not a good argument- cars are built from the ground up for safety, you are wearing the helmet and also about 10 other helmets.

Agree with everything else though, pretty much.

Yes, I meant muons. whoops.

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There's two types of reflections, specular and diffuse. Specular is shiny/glossy objects, the light gets reflected out at the same angle it hit the object like \/. Diffuse (matte) the light gets reflected in all directions. In either case a bit of light is absorbed into the material.

If you've ever seen one of those 'infinity mirrors', it eventually stops when the light is totally absorbed by the glass and mirror.

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Some airports allow you to go to the ‘wrong’ terminal because there are services there. For example help desks, entertainment/relaxation areas for long layovers, children play areas, some have hotels in the airport, lounges, food/restaurants and more. Some airports also have the terminals connected after security, so you can go from one terminal to the other without having to go through security again. It really depends on the airport.

When light hits a surface, there are basically three things that can happen, and the amount each happens depends on the wavelength ("color") of the light, the two materials on either side of the surface, and a bunch of other factors:

• Part of the light is reflected, let's call that part R
• Part of the light is transmitted through the surface, let's call that T
• Part of the light is absorbed, let's call that A

Since those are the only three things that can happen, R+T+A=100% (pretty much, anyway).

On a perfect mirror, nothing is absorbed, nothing is transmitted, and all the light is reflected, so T=0%, A=0%, R=100%.

On a perfectly black surface (like ultrablack or VantaBlack paint), (almost) all the light is absorbed, so T=0%, A=100%, R=0%.

On a perfectly clear window, nothing is absorbed, nothing is reflected, all is transmitted, so A=0%, R=0%, T=100%.

Now, there is no such thing as a perfect surface, so what actually happens is a mix of all three. Like if you look through your windows, most of the light is transmitted, but there is a small fraction that is reflected (you can see what's outside, but you can also see a faint reflection of yourself). There's also a bit that absorbs, but you don't see that.

So yes, every time light reflects, at least part of it is absorbed by the surface and part of it is transmitted, so the reflection is less than the amount of light that hit the surface (it's weaker).

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Whether the reflected light is all the same direction or in in all directions has to do with the roughness of the surface and how it interacts with the light. Something like a mirror reflects all (most) of the light in the same direction, which is why you can see an image in it. That's called a specular reflection. Something like a white wall reflects the light in a mix of random directions, which is called a diffuse reflection. These can be mixed too, like if you look at aluminum foil, where you can see a reflected image but it's a bit blurry. That's a mix of specular and diffuse reflection.

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There are typically secure passages between terminals, ie. for people with connecting flights, etc. Bags all go to a centralized sorting area and there are ways to get bags from terminal to terminal.

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>How come that the biggest tech company products, like Windows OS can be cracked and used for free while apps made by small companies have a strict paywall impossible to break?
>
>I fail to see how their answer was them jumping to conclusion based on what you asked.