\[\boxed{\mathbf{1.}\mathbf{71}}\]
\[\mathbf{Циферблат\ часов - 360{^\circ}.}\]
\[360{^\circ}\ :12 = 30{^\circ} -\]
\[соответствуют\ одному\ часу.\]
\[\textbf{а)}\ 6 \cdot 30{^\circ} = 180{^\circ}\]
\[\textbf{б)}\ 5 \cdot 30{^\circ} = 150{^\circ}.\]
\[\textbf{в)}\ 30{^\circ} \cdot 1 = 30{^\circ}.\]
\[\textbf{г)}\ 4 \cdot 30{^\circ} = 120{^\circ}.\]
\[\textbf{д)}\ 2 \cdot 30{^\circ} + 30{^\circ}\ :2 =\]
\[= 60{^\circ} + 15{^\circ} = 75{^\circ}.\]
\[\textbf{е)}\ 30{^\circ} \cdot 3 + 30{^\circ}\ :2 =\]
\[= 90{^\circ} + 15{^\circ} = 105{^\circ}.\]