Need help!

1) Convert 0.25 mM to mg/mL, assuming the molecular weight of the solute, a protein, is 47,300 g/mol

2) You have a 0.25% (w/v) solution of the detergent SDS (288.4 g/mol). What is the molarity of this solution?

3) You are told to make 75 ml of a 40-fold dilution of 0.25 M potassium oxide stock solution. How many grams of potassium oxide (94.2 g/mol) will be in your final sample?

4)You have 80 mL of 0.4 M Tris buffer, pH 7.5. You pour 20 mL of this buffer into a 100 mL beaker. What is the concentration of the Tris buffer in the beaker?

5)You need to prepare 250 mL of buffer containing 25 mM sodium acetate and 150 mM sodium chloride, pH 4.9. Your source of material is glacial acetic acid and solid sodium chloride (FW 58.44 g/mol). The density of glacial acetic acid (60 g/mol) is 1.05 g/mL. Describe the complete preparation of this buffer using the available material.