Usually, you have a lead guitar and another guitar player, a bass guitar, keyboard/synth, a drumset, and the vocalist. Old rock bands, like Earth Wind and Fire, used to have brass instruments (trumpet and trombone, occasionally saxophone[woodwind]) as part of the instrumentation. It depends on what era of rock you are looking for, but this is the most common instrumentation. Hope this helps! :)
The correct answer is found by grouping 1/3 with parentheses and following the order of operations, with division taking precedence.
9 – 3 ÷ (1/3) + 1
= 9 – 9 + 1
= 0 + 1
= 1
hope this helps!