Livingstone was deliberately silent about the river's angry hippopotamuses, hungry crocodiles, and malaria-carrying mosquitoes. Moreover, in spite of these dangers, he was anxious to return to the Zambezi. He believed that if he could prove it was navigable, it might become a "highway into the interior" and open the continent up to trade. If successful commerce were established, it would compete with and even wipe out the inhumane slavetrade . . . Although Britain had made slavery illegal in 1833, Livingstone was disgusted to discover that others continued to practice it. —Into the Unknown,
Stewart Ross

Choose the answer that best completes each sentence.

By proving that the Zambezi was navigable, Livingstone hoped to .

He felt that slavery was.

From this information, I can tell that he is