I'm struggling with these 7 questions can you explain the answer ?

thank you

1.100L of patient sample was mixed with 300L of diluent and then multiplied the result by 3 to make up for the correct. Is this corrected concentration accurate, too high, or too low? If inaccurate, by what percentage?

1.A calcium standard solution contains 10mg/dL of calcium. What is its concentration in mm/L?

2.How much alcohol is required to prepare 5L of 70% alcohol?

3.A colorimetric method calls for the use of 0.1mL of serum, 5mL of reagents, and 4.9mL of water. What is the dilution of the serum in the final solution?

4.A stock standard solution of urea contains 10mg/mL of urea nitrogen. How much stock (in mL) is needed to prepare 200mL of a working standard containing 20mg/dL of urea nitrogen?

5.An isotonic saline solution contains 0.85% (w/v) NaCl. How many grams of NaCl are needed to prepare 5L of this solution?

How would you dilute a 10M antibiotic solution to a:

a.0.1M solution

b.1.0M solution

c.0.5M solution

d.0.85M solution

6.You have a 100mg/mL stock solution of methionine. You dilute 0.1mL of it in 9.9mL of water.

a.What is the concentration of methionine in the diluted sample?

b.If you now take 2mL of the diluted sample and add 8mL of water, what is the new methionine concentration?

7.Diagram a serial dilution under the following parameters: Use only 3 tubes. The stock solution volume is 0.1mL. You need to achieve a 10^-6 dilution.