How gan i get the slope from a range of cells refered to a desire date?

This is what I have in excel:

ColumnA A B C D
10/17/2009 54 84 15 75
10/17/2009 58 46 48 65
10/18/2009 58 48 78 75
10/18/2009 46 78 45 46
10/18/2009 23 76 85 75
10/19/2009 12 95 95 95
10/20/2009 11 64 84 84

I want to get the SLOPE from Column B only for the dates: 10/18/2009 and
10/19/2009?

Is it possible? how can i do it?


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