Identify the kind of sample that is described. An electronics store randomly pulls the receipts from 20 different days over the past two years and calls all customers who purchased computers on those days to ask about high-speed Internet rates.

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.