Brittany stamps 20 letters in 1
hour. How many hours will it
take her to stamp 380 letters?

380 divide by 20
it will take her 19 hours to stamp 380 letters

You have 2 sides that are 2 cms and you have 6 sides that are 1/2 cm and you have 4 sides that are 1 cm. the smallest sides are 1/2 the medium sized sides are 1 and the smallest are 1/2. so to find the perimeter you have to add them all up together so your answer will be 11 cm's