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If a normal distribution has a mean of 100 and a standard deviation of 20, what percentage of the data falls between 60 and 140?

In this data set the median is:  71 73 84  88 91 91 98 102 104 104 104 105 106 109 110 110 111 112 112 112 113 114      

One of the assays your laboratory carries out requires a 2N HCl.  You have a stock bottle of concentrated HCl with a specific gravity of 1.18 and purity of 36%.  What volume of the concentrated HCl is required to make 250mL of the 2N HCl (MW of HCl = 36.5 Da)?

Which of the following statements correctly compares and contrasts a-priori and a-posteriori methods of reference individual selection? 1. In both methods, exclusion and partitioning take place after sampling and analyte testing. 2. A-priori methods require fewer reference individuals to be studied than a-posteriori methods. 3. Questionnaires for potential reference individuals must be more detailed for a-posteriori methods than for a-priori methods.

Which of the following is the correct sequence to follow in method selection?

Consider the separation of Hb 1, Hb 2, and Hb 3 by cation-exchange HPLC. The initial mobile phase pH causes Hb 1 to have the greatest positive charge, Hb 2 to have minimal positive charge, and Hb 3 to be neutral. Predict the order of elution from the stationary phase as the chromatographic run continues from the initial mobile phase to mobile phases with increasing concentrations of cations. (first to elute to last to elute)

Electro-osmosis is the migration of supporting medium counterions and solvent toward the appropriate electrode. This net flow of counterions and solvent is in the opposite direction to the migration of the macromolecules of interest. Which of the following statements best describes the effect of electro-osmosis?

Which of the following are true about quality control pools?   1. Commercially bought lyophilized material is preferred material due to its stability   2. Clarified frozen or liquid pools typically have lower SD.   3. Pool matrix does not have to match test samples.   4. Liquid pools may experience greater instability errors associated with shipping batches of a lot to a customer.  

Which of the following best describes the effect of nonspecific binding on the detection limit of an immunoassay?  

Considering only the effect of time on electrophoretic separation, the separation of bands ________ with time, and diffusion of bands _______ with time.