A student prepared a stock solution by dissolving 20.0 g of NaOH in enough water to make 150 mL of solution. She then took 15.0 mL of the stock solution and diluted it
with enough water to make 65.0 mL of a final solution. What is the concentration of NaOH for the final solution?
0.769 M
O 0.548 M
1.82 M
1.40 M

Lab reagent, hypothesis test. a reference solution used as a lab reagent is purported to have a concentration of 5 mg/dl. six samples are taken from this solution and the following concentrations are recorded: (5.32, 4.88, 5.10, 4.73, 5.15, 4.75) mg/dl. these six measurements are assumed to be an srs of all possible measurements from solution. they are also assumed to have a standard deviation of 0.2, a normal distributin, and a mean concentration equal to the true concentration of the solution. carry out a significance test to determine whether these six measurements provide reliable evidence that the true concentration of the solution is actually not 5 mg/dl.