How to use a SAC(section Area Coefficient) to calculate wsa?

Hello.

I have now done lots of research but i am unable to figure out how to calculate my keels wetted surface area. for the keel i have the root chord, the tip chord, its span, its thickness/chord ratio and the sac. i assume you must use Simpson's rule but i can't figure out how. can anyone help me asap?

root and tip chord = 1,2 m
Span = 0,975 m
T/C = 7,5%
SAC = 0,66

 

Planform area=span x (root chord + tip chord)/2
Wetted surface area= 2 x planform area + (sectional area at tip)