Question

A protector has two scales upper scale and lower scale​

Answer 1

Answer:

$There \: are \: two \: scales \: marked \: on \\ the \: protractor \: – \: outer \: and \\ inner. \: The \: outer \: scale is \\ marked \: from \: 0° to \: 180° in \\ clockwise \: direction. To \: measure \\ the given ∠MON, we place the \\ protractor \: in \: such \: way that \\ its \: centre \: is \: on \: the \: vertex \: O \\ of ∠MON \: and \: its \: straight \\ horizontal \: edge \: lies \: on the arm \\ ON of the ∠MON \: as \: shown \: in \\ figure.$