The europeans began to colonize areas rich in resources such as rubber and petroleum after

Aging populations can be a problem for developed countries because a) there are fewer younger workers coming into the workforce. b) most older workers demand top-level pay and full benefits. c) many older people are skilled in manufacturing, not technology. d) younger workers cannot find jobs when older people work longer.

The segments shown below could form a triangle.

How did the late 19th century public schools change?