The 3.5mm jack has been around since the 1960s and dual jacks were never thing with home audio afaik. Seems more like a scam invented by airlines to sell compatible earphones.

Exactly.

Ion-exchange resins are also used, but you need to change them regularly.

So, ultimately , it is not a technical problem, but an economic one.

I like the Piano (or I guess any instrument) for this. I know exactly where the keys are for whatever song I'm paying, but it's all subconscious. If I look and actively try to see where the next key is, I can't play. But blind, my fingers just know, after years of doing the same motions.

That explanation is good but I think it underestimates just how much energy it takes to evaporate water, especially at scale. Yeah, you can use a power plant but we're already struggling to generate the power that we need in ways that aren't destructive to the environment.

I wouldn't say it is hard more than it's energy intensive.

Even using the Sun's heat--a solar still-- which is free, takes quite a bit of energy: I guess it depends on scale as well.

To provide potable water for a medium sized city needs a lot of energy. Then, what to do with the salty sludge leftover.

Do you return this to the ocean? It will make the dump site toxic. Do you store all of it somewhere on land? Again, it'll make that area toxic to plants and you don't want rain bringing that salt to the water table, contaminating it.

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It's not hard, in the sense that it's not difficult to do in principle. It's just energy-intensive and therefore expensive, and it requires facilities that are themselves expensive.

My friend's flipper zero would only work with the 2.0 port on his computer.

Are not some power plant near the sea for heating the water?

I actually have a set of commercial headphones that have that technology.

It isn't so much that it's hard to do, but it's hard to do cheaply enough to make it economically feasible. Most methods take a lot of energy, others are relatively slow.

In every case though, desalination on a large scale leaves you with all the salt and minerals that you remove from the water. It's difficult to find somewhere inexpensive to dump those without it screwing up the local ecosystem.

Desalination itself is super easy. Take salt water, evaporate and recondense it to separate the salt and other minerals/etc from the water. You can do it yourself on a stovetop or a campfire.

The problem is that there's no way to scale it easy for the massive demands of human use (personal, industrial, and agriculture). It takes a decent amount of energy to heat up water, and you need to do something with all of the salt you've got left over - no matter where you dump it, you're going to cause environmental problems. Salt is also corrosive so there's longevity problems with equipment/piping/etc but those are relatively minor problems with partial solutions. You can't ignore physics, or just make giant piles of salt disappear.

Desalination isn't particularly hard at a small scale.

The issues with desalination - the area around the plant gets saltier than the rest of the ocean (you have to dump that excess salt somewhere,) which kills all the marine life in the vicinity of the plant. Also, humans need a ton of water, so the plants need to be very large to fulfill all the domestic demand. And since the plants are at sea level, you need large pumps to get all that desalinated water into pressurized pipes - which means you need a lot of power.

Iirc, They're still there by design. Just because people shouldn't smoke doesn't mean someone won't. So it's important there is a safe and obvious place for them to put it out.

I believe there was a plane delayed fairly recently because it was missing an ashtray and it was deemed a safety risk.

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I think that's one thing people generally don't quite understand. I've seen so many people get angry with the airline employees at the terminal when the flight is delayed for some mechanical issue. It's just a bit baffling to me, do you really want to get on a plane that has an issue? It's not like you can just pull over into the median of the engine breaks down.

One time they had to change a tire and it took a well over an hour and some genius was losing his temper and shouting about how quickly he could change his car tire. Okay, yeah buddy lol.

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Okey take two, it Is true i could do better, but i know english only from movies And internet So bear with me here. So, it Is true most stomach noises come from big colum And Is mostly caused by air And/or liquid. If it sound liquidy, expect Nasty, runny poo in like Hour. You can hear your stomach, but you have to be starving, like really more than 4 Hours without food, you Will feel like throwing up And at peak it Will move, making sound And making you feel a lot better for few Hours Again. The stomach wants to push something that Is not there, pushing on itself And making sound.

Tough fish

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Thank ya, kindly!