PLS HELP Which best explains why |–4| = 4?​

a. because -4 is 4 units away from 0.

b. because || means the opposite of

c. it doesn't |-4| = -4

d. because -4=4

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.