What observations did people make which caused them to conclude that the sun, moon and stars went around the Earth?

Acube has a volume of 2011 cubic inches. what is the angle measure between a side of a cube and its interior diagonal?

How does the space charge width change with forward and reverse bias? also, calculate the space charge width for a reverse bias of 4v on a silicon pn junction at t = 300k and doping concentrations of na = 5x1015cm-3 , nd = 5x 1016 cm-3 .

The most important difference between a wedge and an inclined plane is a. their size b. their shape c. how they are used d. what they are made of