What percent of potassium-40 remains undecayed in a rock that is 3.9 billion years old? The 3.9 billion year old rock has undergone three half-lives (3.9 divided by 1.3 = 3). After 3 half-lives, 12.5% of the potassium-40 remains undecayed.
Answer:
D. They form an ionic compound.
Explanation:
The bonds which are produced between a metal ion and a non-metal ion are termed as ionic bonds.
<span>C. obtain and use energy. </span>
The pH will decrease because lemon juice is very acidic meaning it would bring the pH level down to a more acidic value.
They relate because they show that during both natural selection and human evolution u could get a disease during both
