Classify the following angle as acute, obtuse, reflex, right or straight angle.

$275°$

Name the angle formed by the two hands of a clock at $5$ o'clock.

Name the angle formed by the two hands of a clock at $2:30 \mathrm{p}.\mathrm{m}.$

At $9$ o'clock, the angle formed by the two hands of a clock is

At $10$ o'clock, the angle formed by the two hands of a clock.