"alternating"
No, that's Alternating Current.
It is called alternating current (AC) where the flow of electricity reverses direction periodically.
Direct current (DC) is the term used to refer to current that flows in one direction and does not reverse its direction. This is in contrast to alternating current (AC), which changes direction periodically.
Instructions
stage directions
A thermister is a device that changes resistance depending on temperature. A photo resistor changes resistance based on light. Both of these could be used with an amplifying circuit to vary current flow.
Yes you can. The price changes almost daily. Call your local wrecking yard for current prices.
An 'itinerary' is a planned route or journey - which would possibly include driving directions.
Someone who is good with directions is often called "having a good sense of direction."
weathervanes
A panoramic view.
A regular octagon