Each side of a square flower bed is $$2~m~80~cm$ long. It is extended by digging a strip 30cm wide all around it. Find the area of the enlarged flower bed and also the increase in the area of the flower bed.
Five square flower beds each of sides 1 m are dug on a piece of land 5 m long and 4 m wide. What is the area of the remaining part of the land?