John Cuthber

I mean that it's impossible to define your speed with respect to a vacuum. (This makes life rather difficult for traffic police in interstellar space)

If you are heading towards the transmitter really fast, a radio wave is light. And a vacuum can't tell how fast you are going.

The simplest way to achieve the "if nothing else is available" pollination is simply to make sure the ovaries are active a while before the anthers are.

It's "worse" than that. Even just one tree pollenating another will produce many different crosses from countless possibilities- in the same way that we are not (usually) the same as our brothers + sisters. Every year, every seed in every apple will be genetically unique. That's (part of) the reason why they usually propagate commercial varieties from cuttings. I understand that some plants will self pollenate, but leave it to the "last minute" They only do it if no other pollen is received. They seem to have evolved to recognise that evolution is a good thing. This makes them "better informed about evolution" than some people I know of.

There are some reagents (Like LiAlH4) which get used a lot in exam questions and textbooks, but not so much in real life. On paper they do the job. In practice they tend to set your lab on fire, and chew through your budget. Cr(VI) based oxidants are a bit too carcinogenic to be popular in industry. (Yes, I know, there are exceptions. The difference is that IiAlH4 might be your first choice in an exam, but it might not be in industry.

" how can be advertised at more intensity than the sales of automobiles with a $50k sticker each ?" How often does the typical user buy (1) Viagra (2) A car ? The big cost of bringing a drug to market is all the testing. Having sold many pills at $40 they have paid for that. Now they only have to cover their costs, so the price has dropped It's interesting to look at the variation of price between manufacturers. https://bnf.nice.org.uk/drugs/sildenafil/medicinal-forms/ And now, it's just a commodity like bread. It gets advertised so people buy a particular brand.

If you dissolve "aluminium" in alkali it turns black because other elements present in the alloy (notably copper) don't dissolve and very finely powdered metals are black. Hydrogen gas is not "choking" but a spray of sodium hydroxide solution is.

They say the best time to plant a tree is 100 years ago and the second best time is now. I think the same logic applies to removing them. Having said that, I guess cutting them while they are dormant will trouble them less than when they are in full swing. You can find data on when is a good time to prune trees; and then do your best not to follow it. https://silveroaktreesurgery.com/article/a-guide-to-which-uk-trees-to-prune-in-late-spring-and-summer

They seem to have found a less bad way of doing the wrong thing. And, among other issues, helium is not a renewable resource.

" most of us on the outside of science looking in are getting a little tired of this big bang B.S. It's time to move on" Yes. Move on from being "outside of science" by learning a bit and coming inside.

If the objects are air molecules, the answer is clearly "no". As MigL has pointed out, the question needs work.

They were when I got my IQ tested at school...

The penetration depth of "cooking" microwaves into food is variable but typically about 3 cm. That for the IR from a grill is less than a millimetre. So, for an item less than a few cm thick, it is heated "in the middle" by the microwaves. The outside is heated more than the inside, but, unlike a conventional oven, heat is generated inside the item, rather than being conducted from the outside.

The results are in. Apparently 17000 dead as a consequence of HCQ. https://www.sciencedirect.com/science/article/pii/S075333222301853X

The big difference in colour is caused by soot in the first flame. Because there's not much oxygen, some acetylene decomposes to carbon which is heated to incandescence. The blue colour of the other flames is due to emissions from hot C2 molecules (if I recall correctly). A Bunsen flame would be a lot hotter if you could run it with acetylene. It's a fuel with a higher energy density.

The biggest difference is between the first flame and the subsequent ones. That's largely because when gas burns in air it has to heat up the nitrogen that comes along with the oxygen. Feeding the flame with pure oxygen avoids that.

The magnesium in your diet is likely to be largely present as /converted to free magnesium ions as soon as it hits the acid in your stomach. So this magical counter-ion is irrelevant. But I'm amused that threonate's wiki page led me to this. https://en.wikipedia.org/wiki/Dickkopf It may be childish of me, but I think that name is funny.

Ethyl cellulose is not natural.

Does German have an equivalent of the 11 (or more) ways in which English pronounces "ough"?

Some clearly do. Camphor and menthol have strong odours. Diffusion in solids it slow, but it does happen.

If it's really important then you need thermostatic heating /cooling and a constant current driver.

Threshold current. Lifetime sees mainly temperature dependent so a reduced power presumably increases lifetime https://www.newport.com/medias/sys_master/images/images/hbc/h43/8797050241054/AN33-Estimating-Laser-Diode-Lifetimes-and-Activation-Energy.pdf

Can you let us know your explanation? Still waiting.

So what? Had anyone said they couldn't? Do you realise that humans did not evolve from chimps? Nobody really thinks they did. So, what you are doing is presenting a straw man argument. So, once again... since this is a science site, I expect you to provide the extraordinary evidence for your extraordinary claim.

For teh sake of discussion, it's unlikely that Alex was ever told about a toy doll. But if you showed him a green doll and asked what colour it was then (so I'm told) he would tell you it was green, He could tell you that a coke can was red without needing to be told. What Green meant to Alex was the same as it means to you or me.