What is your acceleration while sitting in your chair. the latitude of corvallis is 44.4˚.?

 You can start with the equations you know 

a=v^2/r = (2pi*r/T)^2/r = 4pi^2r/T^2 

Radius of earth (R) = 6378.1 km 
Time in one day (T) = 86400 seconds 
Latitude = 44.4 degrees 

If you draw a circle and have the radius going out at a 44.4 degree angle above the center you can then find the r. 

r=Rcos(44.4) 
r=6378.1cos(44.4) 
r= 4556.978198 km or 4556978 m 

Now you can plug this value into the acceleration equation from above... 

a= 1.8*10^8/7.47*10^9 
a= .0241 m/s^2