<u>Answer:</u> The mass of methylene blue that must be weighed is 
<u>Explanation:</u>
To calculate the mass of solute, we use the equation used to calculate the molarity of solution:

We are given:
Molarity of solution = 
Molar mass of methylene blue = 319.85 g/mol
Volume of solution = 100.0 mL
Putting values in above equation, we get:

Hence, the mass of methylene blue that must be weighed is 
The element that has a complete valence electron shell is argon (Ar) since it is a noble gas in the last group on the periodic table.
Answer:8
Everything after the decimal place is a significant figure here
Answer:
filtration is the process of using a filter to remove solids from liquids or gasses.
Example:
an example of this is tea.
Asexual is growth and repair , 4 daughter cells and cell divides once dna replicates and the rest is sexual reproduction besides divides one