"the key traits of early rock and roll were the driving backbeat, electric guitar, and loud, amplified volume."

The correct answer for the blanks is : Microphone
Since rock and roll's music is really loud and fast, it's almost impossible for the singer's voice to be heard if he's not using a microphone. That's why it's a must.

If he tries to grape you then get a grape and grape him back

Architectural pathway uses cad.