For how long can the Nile crocodile, remaining fully inactive, hold its breath under the water?

The Nile crocodile is an African crocodile, the largest freshwater predator in Africa, and may be considered the second-largest extant reptile and crocodilian in the world, after the saltwater crocodile. The Nile crocodile is quite widespread throughout sub-Saharan Africa, occurring mostly in the central, eastern, and southern regions of the continent, and lives in different types of aquatic environments such as lakes, rivers, and marshlands.

Nile crocodiles normally dive for only a few minutes at a time, but can swim under water up to 30 minutes if threatened, and if they remain fully inactive, they can hold their breath for up to 2 hours (which, as aforementioned, is due to the high levels of lactic acid in their blood). They have a rich vocal range, and good hearing. Nile crocodiles normally crawl along on their bellies, but they can also "high walk" with their trunks raised above the ground.