Average values for several parameters based on date and time ranges

So the easiest is to use the function AVERAGEIFS.  Here are 2 examples:

a) using ranges:

=AVERAGEIFS($G$3:$G$18,$F$3:$F$18,">="&B$3+B$4,$F$3:$F$18,"<="&B$3+B$5)

b) using table reference (need to format datatable using Format as Table)

=AVERAGEIFS(Table1[Parameter 2],Table1[Date - Time],">="&B$3+B$4,Table1[Date - Time],"<="&B$3+B$5)

as you copy down/right you will have to update some of the references accordingly