Answer
Option 'b' is right
(b) $76.6^{\circ}$
Work Step by Step
To convert $76^{\circ} 36'$ to decimal degrees, let's break it as-
$76^{\circ} 36'$ = $76^{\circ}$ + $36'$
Now on dividing $36'$ by 60, we have the number of "decimal degrees" equivalent
to $36'$ (as $ 1^{\circ} = 60'$)
Therefore
$76^{\circ} 36'$ = $76^{\circ}$ + $(\frac{36}{60})^{\circ}$
$76^{\circ} 36'$ = $76^{\circ}$ + $0.6^{\circ}$
$76^{\circ} 36'$= $76.6^{\circ}$
