11) Working alone, it takes Willie seven hours to paint a fence. Ndiba can paint the same
fence in eight hours. How long would it
take them if they worked together?
A) 3.73 hours B) 2.92 hours
C) 3.49 hours D) 3.56 hours

Is there a direction u in which the rate of change of f(x,y)equals=x squared minus 3 xy plus 4 y squaredx2−3xy+4y2 at p(1,2) equals 14? give reasons for your answer. choose the correct answer below. a. no. the given rate of change is smaller than the minimum rate of change. b. no. the given rate of change is larger than the maximum rate of change. c. yes. the given rate of change is larger than the minimum rate of change and smaller than the maximum rate of change.