Find the area of a regular pentagon with apothem length of about 10.3 meters. round to the nearest tenth if necessary.

options:

77.3 units2

386.3 units2

154.5 units2

772.5 units2

The perimeter of △cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.