Actividades económicas de las regiones polares

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.

What is the largest river in the united states?

Regions are always defined by a. climate b. many different factors c. mountain ranges d. continents & bodies of water