Answer:
93.33%
Explanation:
Thorium is a radioactive element with a molecular weight of 232g/mol. Thorium is very stable and can have 14.05 billion years of half-life period. Every half-life passed, the parent compound mass will be decayed by half. If the age of the rock is 1.4 billion years, then the amount of the parent compound will be:r = ½^(time elapsed/half-life)
r = ½^(1.4bil years/14.05 bil years)
r = ½^(0.0996)= 0.9333
r= 93.33%
The rock will have 93.33% of the parent compound and 6.67% of the decayed compound.
Answer: Option (b) is the correct answer.
Explanation:
When the cake is baked then due to the heat provided to it there will occur movement of its molecules.
As a result, molecules will gain kinetic energy due to which there will occur collisions between them.
Also, 
Hence, more is the heat provided to the cake more will be the kinetic energy of its molecules due to which when we touch it, it feels hot.
Thus, we can conclude that molecules in the cake are moving faster than molecules in the skin, best explains why the cake feels hot.
Keep trying you will get if you keep trying ok
Answer:
A) It contains a lot of matter.
It’s either a or b, but I’m not sure which one it really is, but I hoped I helped a little /:).