Answer
1
Work Step by Step
Given expression
= 2 $\sin( 90^{\circ} - z)$
= 2 $\sin(90^{\circ} - 60^{\circ})$
( replacing $ z$ with $60^{\circ}$)
= 2 $\sin 30^{\circ}$
= 2 $\times (\frac{1}{2})$
( substituting exact value of $\sin 30^{\circ}$)
= 1