Assayed for LDH activity were 5 microliters of a sample that was diluted 6 to 1. The activity in the reaction vessel, which has a volume of 3 mililiters, is 0.30 U. What is the ΔA/min observed? What is the relative activity of the original sample?

Question

Here are the formulas:

U=(ΔA/Δmin)/((6220 M^-1cm^-1)(1cm))X 10^6 micrometer/M X 3X10^-3 L

relative activity:

U/mL= U/(volume of fraction assayed) X dilution used, if any.

I have an answer for the first part. I got 0.622. The second part, i don't know how to put the dilution into the equation.

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