Answer:
a) 6.426 grams of potassium bromide student must weigh.
b) The correct answer is option a.
Explanation:

a) Concentration of potassium bromide = c = 0.180 M
Moles of potassium bromide = n
Volume of the potassium bromide solution = 300 mL = 0.3 L


Mass of 0.054 moles of potassium bromide :
= 
6.426 grams of potassium bromide student must weigh.
b) Drying of flask in drying oven. This is because solution will be prepared by adding water after adding solute. So drying the flask will be not required.
An instrument with high amplitude has loud sound. An instrument with low amplitude has soft sound.
Answer:
I think that it might be cytoplasm
Explanation:
I got this from google
Cytoplasm is a thick solution that fills each cell and is enclosed by the cell membrane. It is mainly composed of water, salts, and proteins.
Methylation is a process that involves Mercury metal. Methylation is a process by which a methyl groups are added to the DNA molecule. when it occurs it can change the activity of a DNA segment without changing the sequence, additionally, when located in a gene promoter it may act to repress gene transcription.