Search google? Not knowing anything about EC50 or dose-response
graphs, I found enough information to educate myself in about 5 mins.

Then, use something like Interactive Chart
http://www.tushar-
mehta.com/excel/software/interactive_chart_display/index.html

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Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

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