What is the area of this composite figure? 4 cm
7.5 cm
15.5 cm
18 cm
135 cm?
O 207 cm?
249 cm?
O 279 cm?

The pyraminx is a rubik's cube-type toy in the shape of a tetrahedron. the pyraminx shown below has edges 15\,\text{cm}15cm long and vertical height h=12.2\,\text{cm}h=12.2cm. the triangle drawn with dashed lines is a right triangle. what is the distance rr? round your answer to the nearest tenth.