The answer is 3.5 × 10^-3
A typical human hair is about 1 million carbon-12 atoms JUST IN WIDTH.
Answer:1) Volume of
required is 55.98 mL.
2) 0.62577 grams of
is produced.
Explanation:

1) Molarity of 
Volume of 
Molarity of 
Volume of 


According to reaction, 1 mole of
reacts with 3 mole of
, then, 0.0041985 moles of
will react with:
moles of
that is 0.0125955 moles.


Volume of
required is 55.98 mL.
2)

Number of moles of
According to reaction, 3 moles of
gives 1 mole of
, then 0.004485 moles of
will give:
moles of
that is 0.001495 moles.
Mass of
=
Moles of
× Molar Mass of 
= 0.001495 moles × 418.58 g/mol = 0.62577 g
0.62577 grams of
is produced.
The absence of an unbalanced force, an object at rest will stay at rest and an object in motion will stay in motion.
Answer: 2) 0.21 mole H2O
3) 0.50 mole K2O
4) 123 g Ca( NO3)2
Explanation: solution attached.
For number 2 to find the number of moles of H2O just divide the given in molecules with the Avogadro's number.
For 3 convert grams of K2O to moles by using 1 mole of K2O is equal to the molar mass of K2O
For number 4 moles to grams. Same process with number 3