Okay, here we have this:
Considering the provided rectangle, we are going to calculate the requested perimeter, so we obtain the following:
Remember that the perimeter of a figure is equal to the sum of all its sides, so we have:
Perimeter of the rectangle=b+b+h+h
Perimeter of the rectangle=2b+2h
Perimeter of the rectangle=2(b+h)
Perimeter of the rectangle=2(12.6 cm+6.4 cm)
Perimeter of the rectangle=2(19 cm)
Perimeter of the rectangle=38 cm
Finally, we obtain that the perimeter of the rectangle is 38cm, so the correct answer is the option A.