In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

It became easier to move around in non-deep water thanks to what living entity?, Context: The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location.
Sir William Thomson

Why are areas in Neolithic sudan no longer settled?, Context: During the Neolithic Era, before the onset of desertification, around 9500 BCE the central Sudan had been a rich environment supporting a large population ranging across what is now barren desert, like the Wadi el-Qa'ab. By the 5th millennium BCE, the people who inhabited what is now called Nubia, were full participants in the "agricultural revolution", living a settled lifestyle with domesticated plants and animals. Saharan rock art of cattle and herdsmen suggests the presence of a cattle cult like those found in Sudan and other pastoral societies in Africa today. Megaliths found at Nabta Playa are overt examples of probably the world's first known archaeoastronomy devices, predating Stonehenge by some 2,000 years. This complexity, as observed at Nabta Playa, and as expressed by different levels of authority within the society there, likely formed the basis for the structure of both the Neolithic society at Nabta and the Old Kingdom of Egypt.
now barren desert

Who was born later, Jefferson or Mark David Hall?, Context: Jefferson's opponents said his position was the destruction and the governmental rejection of Christianity, but this was a caricature. In setting up the University of Virginia, Jefferson encouraged all the separate sects to have preachers of their own, though there was a constitutional ban on the State supporting a Professorship of Divinity, arising from his own Virginia Statute for Religious Freedom. Some have argued that this arrangement was "fully compatible with Jefferson's views on the separation of church and state;" however, others point to Jefferson's support for a scheme in which students at the University would attend religious worship each morning as evidence that his views were not consistent with strict separation. Still other scholars, such as Mark David Hall, attempt to sidestep the whole issue by arguing that American jurisprudence focuses too narrowly on this one Jeffersonian letter while failing to account for other relevant history

Mark David Hall