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. As you move down the table, every row adds an orbital.
Answer:
N
Explanation:
Using the formula you gave:
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Answer:
Check image.
Explanation:
This is what my solution is, not a professional tutor so take my answer with a grain of salt and check.
Your pendulum does a complete swing in 1.9 seconds. You want to SLOW IT DOWN so it takes 2.0 seconds.
Longer pendulums swing slower.
You need to <em>make your pendulum slightly longer</em>.
If your pendulum is hanging by a thread or a thin string, then its speed doesn't depend at all on the weight at the bottom. You can add weight or cut some off, and it won't change the speed a bit.