Therefore, a PVC pipe can be sheathed with two sticks, 2x 1.6=3.2 (three sticks is 4.8m, which means more than 4m).
28 pieces need 28/2= 14 PVC pipes.
When PVC pipes can be connected and used, the total length of PVC should be greater than or equal to the total length of rods.
The total length of the stick is 28 * 1.6 = 44.8 meters.
The requirement for Pvc pipes is 44.8÷4= 1 1.2, and the number of pipes is an integer, so 12 pipes is enough.