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Returns a Duration representing n minutes. This function takes a number and converts it into a Duration type value, expressed in minutes.
minutes(42) returns a duration of 42 minutes. Minutes([Test Length in Minutes]) converts the numeric value in the Test Length in Minutes field into a duration expressed in minutes. The number doesn't change, just the data type. [Start Time] + minutes(90) returns the time of day that 90 minutes after the time of day in the Start Time field.