Answer 2: Yes, radiometric dating is a very accurate way to date the Earth.
We know it is accurate because radiometric dating is based on the radioactive decay of unstable isotopes.
Though they are very tiny, polonium radiohalos have a huge message that cannot be ignored.
They point to a catastrophic origin for granites, consistent with the biblical timeframe for earth history and God’s judgment during the Flood.
By dating rocks of known ages which give highly inflated ages, geologists have shown this method can’t give reliable absolute ages.
Many geologists claim that radiometric “clocks” show rocks to be millions of years old.
Hope that helps, and please ask if you'd like more details! I think that I will start by answering the second part of your question, just because I think that will make the answer to the first question clearer.
Radiometric dating is the use of radioactive and radiogenic (those formed from the decay of radioactive parents) isotopes (isotopes are atoms of the same element that have different numbers of neutrons in their nuclei) to determine the age of something.However, to read any clock accurately we must know where the clock was set at the beginning.Most people think that radioactive dating has proven the earth is billions of years old.The ratio of the parent to daughter then can be used to back-calculate the age of that rock. The reason we know that radiometric dating works so well is because we can use several different isotope systems (for example, Uranium-Lead, Lutetium-Halfnium, Potassium-Argon) on the same rock, and they all come up with the same age.This gives geologists great confidence that the method correctly determines when that rock formed.Because geochronologists want to measure isotopes with different masses, a mass spectrometer works really well for dating things.