2. What do you call the start of the river?

At a continent-continent convergence,

Which of the following statements best explains why there tends to be a greater number of large cities in southern africa than the east africa

Some gamma ray bursts are hypothesized to come from mergers of neutron stars or black holes. if this hypothesis is correct, what else should we in principle be able to detect from such mergers? a. gravitiational waves b. x-ray bursts c. significant disruption of gas thousands of light-years away in the surrounding galaxy d. an "afterglow" of bright visible light, lasting for weeks