i just need a final answers

Problem 15. (1 point) Use the contour diagram of f in the figure below to decide if the specified directional derivatives below are positive, negative, or approximately zero. (a) At point (2,2), indirection i: jfy is +? * positive * negative * approximately zero (b) At point (0, -2}, in direction ? I 1s +? * positive * negative * approximately zero (c) At point (1,1), in direction i +?: fz is *? * positive * negative * approximately zero (d) At point (1,1), in direction i + _r} feis *? * positive * negative * approximately zero (e) At point (0, 2). in direction i +2?; Iz is *? * positive * negative * approximately zero . C e (f) At point (0, 2), in direction i 27: +? fais * positive * negative * approximately zero Problem 16, (1 point) A car is driving northwest at v mph across a sloping plain whose height, in feet above sea level, at a point N miles north and E miles east of a city is given by hN.E)=2750+25N + 25E. {a) At what rate is the height above sea level changing with re- spect to distance in the direction the car is driving? rate = (b) Express the rate of change of the height of the car with respect to time in terms of v. rate = Problem 17. (1 point) You are climbing a mountain by the steepest route at a slope of 15% when you come upon a trail branching off at a 45 angle from yours. What is the angle of ascent of the branch trail? angle = Problem 18, (1 point) The temperature at any point in the plane is given by T(x,y) = 170 x4y 4 (in degrees) (a) What shape are the level curves of 77 A, parabolas B. ellipses C. hyperbolas D. lines E. circles E none of the above (b) At what point on the plane is it hottest? What is the maximum temperature? (c) Find the direction of the greatest increase in temperature at thepoint (3,2). What is the value of this maximum rate of change, that is, the maximum value of the directional derivative at (3,2)7 (d) Find the direction of the greatest decrease in temperature at the point (3.2). What is the value of this most negative rate of change. that is, the minimum value of the directional derivative at (3,2)? Problem 19, (1 point) At a certain point on a heated metal plate, the greatest rate of temperature increase, 6 degrees Celsius per meter, is toward the northeast. If an object at this point moves directly north, at what rate is the temperature increasing? degrees Celsius per meter Problem 20. (1 point) Use the contour diagram for f(x,y) shown below to esti- mate the directional derivative of f in the direction at the point P. (a) At the point P = (2,2) in the direction = j, the directional derivative is approximately (b) At the point P = (3,2) in the direction V = i, the directional derivative is approximately _____ (c) At the point P = (4,1) in the direction = (i+ ) /v/2, the directional derivative is approximately _____ (d) At the point P = (4,0) in the direction Vv = i, the directional derivative is approximately _____ 08 o (Click on graph to enlarge)