I believe I figured
out a and b. For a) any vector perpendicular to the gradient at (1,1). This is <-1/8, 1/4> and <1/8,-1/4> divide by magnitude of each vector. For b) it will be the gradient at (1,1) as a unit vector, then dot this with the gradient at (1,1) to get slope. For c) I set up 0.25=<-1/8,-1/4> dot <a,b>, but I'm not sure how to get the exact solutions for a and b. For d) Should I take the gradient of r(x,y) at t = 0?