Please help im so stuck on this n

Step-by-step explanation:

4) d = 12 cm; r = 12/2 = 6cm ; h = 5 cm

S.A = 2πr(r + h)

      = 2* 3.14 * 6 * (6 + 5)

     = 2 * 3.14 * 6 *11

    = 414.48 cm²

5) d = 8 cm ; r = 8/2 = 4cm ; h = 7cm

S.A = 2πr(r + h)

      = 2 *3.14 * 4 * (4 + 7)

     = 2 * 3.14 * 4 * 11

    = 276.32 cm²

6) r = 4 cm ; h = 6cm

SA = 2πr(r +h)

     = 2 * 3.14 * 4 * 10

     = 251.2 cm²

7) Area of front and back =

                                         = base  * height

SA = (front and back) + Base + left + right

          = 4* 3 + (8*3) + (8*4) + ( 8*5)

         = 12 + 24 + 32 + 40

         = 108 cm²

8) SA =  (front and back) + Base + left + right

          =  (8 * 6) + (12*6) + (12*8) + (12*10)

         =  48 + 72 + 96 + 120

        = 336 cm²

9) SA =  (front and back) + Base + left + right

          =  (12 *5) + (8*5) + (8*12) +(8*13)

         = 60 + 40 + 96 + 104

          = 300 cm²

c. 4 1/4 pounds