As @Civil_Guy said, the kilogram was redefined in terms of fundamental constants, using a device called a Kibble balance. In the run-up to the redefinition, the “counting atoms” approach was a leading contender.
Despite the Kibble/Planck-constant approach ultimately being selected, resolving discrepancies between the two techniques is an active area of research.
You could, but we (geologists) generally prefer more specificity than that if possible. Like “basalt” or “andesite”.
“igneous” and “volcanic” aren’t synonyms.
Magma is what it’s called when it’s still deep underground.
That’s why with inertial (i.e. dead-reckoning) navigation you might find it advisable to use three instruments and go with majority rule.
If all three disagree (or if one fails) than it’s clear you have no idea where you are and it’s time to determine your position using another method entirely (like GPS) and recalibrate the inertial instruments.
I know you’re summarizing mightily and only partly serious. I’d say it more like
If all 3 are seemingly working normally they’ll still disagree some. You assume you’re somewhere in/near the triangle formed by the 3 fixes. The smaller and more equilateral the triangle, the happier the nav officer is.
If two agree to typical tolerances and the third is a long way away, or stone dead, strike an ellipse around 2 two positions you have. But with a larger than usual confidence interval. And start worrying.
If they’re each in major disagreement w the other(s), you are well and truly lost until you come up w some alternate means to fix your position.
I recommend avoiding partially hydrogenated water.
After a steady online diet of watching preparedness videos, this hurts my brain.
After thinking about it, I’m surprised there wasn’t a reverse transcriptase step.
I demand isotope separation. I only drink water made from pure 16O. Anything else would… sap and impurify my precious… bodily fluids.
I did chuckle that after exposure to the neutron source, it’s now an activated carbon filter! 
Overly hydrogenated water is also bad.
As is overly oxygenated water. Not so much the kind with oxygen gas dissolved in it (which is fine), but the kind with an extra oxygen atom in each molecule (aka hydrogen peroxide).
Sure, but Santa does recommend it. Why should we take your word over his?
Welp. I’m embarrassed to admit I was aiming for hydrogen peroxide myself.
I interpreted @Dr.Strangelove’s description backwards, then wrote the opposite trying to be clever.
Well, the whoosh is on me. Turns out water is H2O, not O2H. Who knew?! 
\mathrm{H_3O^+} isn’t palatable in very large quantities, either
Good one! (And nice formatting! I’ve not seen that method before.)
Turns out you were right after all, @LSLGuy.
It’s scarier than you may know. Oldie but goodie (gives a brief history of DHMO trolling):
Who First Alerted the World to the Dangers of Dihydrogen Monoxide?
How did the chemist die? When his friend ordered H2O at the bar, he ordered H2O too.
Billy was a chemist’s son
But Billy is no more
For what he thought was H2O
Was H2SO4
[ sigh ] But that still doesn’t change the fact that I have four extra ones around my waist…