When do many grains of sand become a pile of sand?

The red square is a famous historical site that is located in

What is a problem natives in both bolivia and peru face? a. extreme poverty c. discrimination b. limited access to resources d. all of the above

Zac wanted to determine the measure of r and of ? r in the triangle below. to fine the measure of r, zac sets up the problem.42^2 + 24^2 = r 2. determine whether zac set the problem up correctly.