Answer:
Since the tape has extra electrons, it has a negative charge. When you move your finger close to the tape, electrons in your skin are repelled and move away. This makes the skin on your finger tip have a slight positive charge. Since positive and negative attract, the tape moves toward your finger.
The empirical formula is Ca₃P₂O₈.
<em>Assume</em> that you have 100 g of the compound.
Then you have 38.76 g Ca, 19.97 g P, and 41.28 g O.
Now, we must convert these <em>masses to moles</em> and <em>find their ratio</em>s.
If the number in the ratio are not close to integers, you <em>multiply them by a numbe</em>r that makes them close to integers.
From here on, I like to summarize the calculations in a table.
<u>Element</u> <u>Mass/g</u> <u> Moles </u> <u> </u><u>Ratio </u> <u> ×2 </u> <u>Integers</u>
Ca 38.76 0.967 07 1.4998 2.9995 3
P 19.97 0.644 82 1 2 2
O 41.28 2.580 0 4.0011 8.0023 8
The empirical formula is Ca₃P₂O₈.
Explanation:
It is given that,
Initial orbit of electrons, 
Final orbit of electrons, 
We need to find energy, wavelength and frequency of the wave.
When atom make transition from one orbit to another, the energy of wave is given by :

Putting all the values we get :

We know that : 
So,

Energy of wave in terms of frequency is given by :


Also, 
is wavelength
So,

Hence, this is the required solution.
-III I
NH₄⁺
V -II
N₂O₅
I V -II
NaNO₃
-----------------------
-3 +5 +5
Granite forms when
magma cools slowly underground. Granite is an intrusive igneous rock.
The answer is letter B. granite is composed mostly of quartz and feldspar with
minor amounts of mica, amphiboles and other minerals.