I need help with these questions

Suppose that over a certain region of space the electrical potential V is given by V(x. y. 2) = 7r - Ary + ryz. Find the rate of change of the potential at P(1. 3, 7) in the direction of the vector v=i-j -k. 23 1. V3 2. -23 23 3. V3The temperature at a point (r, y) in the plane is T(x, y) C. If a bug crawls on the plane so that its position in the plane after t minutes is given by (r(), /(t)) where V2 +t. y = 2 + determine how fast the temperature is rising on the bug's path at f = 2 when T2 (2, 3) = 8. Ty (2. 3) - 6. 1. rate = 7 C/min 2. rate - 9 C/min 3. rate = 6' C/min 4. rate - 5 C/min 5. rate - 8 C/minIf f (x, y) = 1 + 4y, use the gradient vector Vf(5, 1) to find the tangent line to the level curve f(r, y) = 29 at the point (5, 1). 1. 2x + 8y = 29 2. 5x + 4y = 29 3. 101 - 8y = 29 4. 10r + 8y = 29 5. 5r - 4y = 29Find the directional derivative of f (I, y) = Te by at the point (7, 0) in the direction indi- cated by the angle 0 NO 1. -6 2. 6 3. -42 4. 42 5. 0Suppose that over a certain region of space he electrical potential V is given by V(r, y, 2) = 7x2 - Ary + ryz. Find the rate of change of the potential at P(1, 3, 7) in the direction of the vector v=i+j -k. 23 1. V3 2. -23 23 3