Last year, 7600 athletes finished a marathon in lakeside, this year there were 6156 athletes finishing. what is the percent decrease in the number of finishers?

What’s the domain of this function? fastttt

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

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.