Which of the following best describes the expression 12(x + 3)?

a) the product of a constant factor 12 and a 2-term factor x + 3
b)the sum of a constant factor 12 and a 2-term factor x + 3
c)the sum of constant factors 12 and x + 3
d)the product of constant factors 12 and x + 3

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.