Answer:
Rock Y
Explanation:
The rock that is older shall be determined based on the number of half lives it has witnessed. A half life is simply the amount of time required for a sample to decay to half of its original mass.
Rock X
From 100% uranium, it decays to 50% uranium. This means it went through just one half life.
Rock Y
From 100% uranium to 25% uranium
100 --> 50 (first half life)
50 --> 25 (second half life)
This means it wen through 2 half lives.
Rock Y is older than Rock X
In my opinion I believe it would be motion because depending on how fast the person is going it would determine the outcome of the race
Answer:
All of the elements in a period have the same number of atomic orbitals. For example, every element in the top row (the first period) has one orbital for its electrons. All of the elements in the second row (the second period) have two orbitals for their electrons.
Explanation: