Different can be a lot or not much. A lot could be a total opposite of something that has happened before or is happening now.
Some restaurants change their menus according to lunch or dinner. Some have the same menu all day. Some are only open for one meal. It depends.
Mainly because of the axial of the earth. When it is summer in the northern hemisphere it is winter in the southern.
Different 'from' is correct.
Wires are built to a standard (a 'gauge'). Thicker wires can withstand more current.