The activities on this list were a result of which physical feature? A. Deep harbors along the east coast of South America
B. Rain forest regions in the northern interior of South America
C. Large areas of grasslands in the southern regions of South America
D. Major mountain ranges through the western areas of South America

H=   2(area/a+b)h= 2(144/a+b)h= 2(144/18+18)h= 2(144/36)h= 2(4)h=8

In a right-angled triangle: 1- the hypotenuse is the longest side2- we can apply pythagorean rule which states that: (hypotenuse)^2 = (side1)^2 + (side2)^2for the given triangle,longest side is 15 cm  side1 = 9 cmside2 is 12 cm  to check whether the triangle is right-angled or not,compare (15)^2 to the summation of (9)^2 and (12)^in other words, compare 225 to the summation of 81 and 144if they are both equal, then the triangle is right-angles, otherwise, it is not.you haven't provided the diagram showing her work, so i cannot tell the choice. however, apply my explanation to the question you have.

1. d: oceanic crust is thicker and contains a lot of granite2.d: where two continental plates are colliding  3.b.contour boundaries4.b.plates that are attracted to each other by gravity5.a.as two continental plates collide along a convergent boundary, mountains are formed.