Which expression best estimates 6 3/4 divided by 1 2/3 A 7 divided by 2
B 6 divided by 1
C 8 divided by 3
D 3 divided by 2

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.