The answer is D.
I am pretty sure, I hope this helps
Answer:
Radioactive isotopes are unstable and will decay. ... The isotopes will decay into a stable isotope over time. Scientists can tell how old the rock was from looking at the radioactive isotope's half-life, which tells them how long it would take for there to be half the radioactive isotope and half the stable isotope.
Answer:
True
Explanation:
Deep space telescopes are fitted with the faint object cameras, that are way better than ground-based spectroscopically functioning telescopes. The Subaru telescope at Hawaii observed the faintest object ever from a ground-based telescope. But when compared to other deep-space telescopes like Hubble's deep space telescopes it's very small. They have reached up to a magnitude of 31 , which observes 20 times fainter objects .
