How many times in a day are the hands of a clock at a right angle?

If March $2, 1994$ was a Wednesday,what day was January $25, 1994$?

The time shown by a clock was $2$ o'clock. After a certain time, the mirror image shown by the clock was $15$ minutes past $7$. What is the time lag between the two times?

At what time between $7$ and $8$ o'clock will the hands of a clock be at a right angle?

At what time between $7$ o'clock and $8$ o'clock will the hands of a clock be in the same straight line but,not together?

My watch gains $5$ seconds in $3$ minutes. It was set right at $7$ am. In the afternoon of the same day,when the watch indicates quarter past $4$ o'clock,what is the true time?