Which river feeds the highest waterfall in Africa?

In which country is the Tis Issat Waterfall located? In which US state is the Multnomah Falls located? What is the name of the waterfall on the border of Zambia and Zimbabwe? What is the name of the waterfall on the Argentina-Brazil border? What is the height of the Huangguoshu Waterfall in China? Which waterfall is also known as 'Kerepakupai Merú'? What is the name of the highest waterfall in Norway? In which province is the Helmcken Falls located?