Answer:
plug-in
Explanation:
A Plug-in is a software that provides additional functionalities to existing programs. The need for them stems from the fact that users might want additional features or functions that were not available in the original program. Digital audio, video, and web browsers use plug-ins to update the already existing programs or to display audio/video through a media file. Plug-ins save the users of the stress of having to wait till a new product with the functionality that they want is produced.
Answer:
Sheave wheel and hoist cable
Explanation:
The sheave wheel is a pulley wheel that sits above the mine shaft. The hoist cable passes over the sheave wheel and then down the shaft of the mine. The sheave wheel reduces the sliding friction of the mine cable. The head frame is the structure that supports the sheave wheel.