need help can someone explain this problem
please.

The perimeter = the sum of the length of each side.
The shape with missing sides is a rectangle, and we know that rectangles have equal opposite sides.
The top of the rectangle = 3.5 and now we know all the values of each side.
3.5 + 3.5 + 2.4 + 2 + 2 = 13.4 cm.
The perimeter = 13.4cm