If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Two boys wish to cross a river. The only way to get to the other side is by boat, but that boat can only take one boy at a time. The boat cannot return on its own, there are no ropes or similar tricks, yet both boys manage to cross using the boat.

How?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes

I’m tall when I’m young, and I’m short when I’m old. What am I?

Remove two matchsticks to make the below equation correct.

In a basket of apples,
when counted in twos, there was one extra
when counted in threes, there were two extra when counted in fours, there were three extra
when counted in fives, there were four extra
when counted in sixes, there was five extra.

However, if the apples were counted in sevens, no extra apple was left. Can you calculate the minimum number of apples that were present in the basket?

You measure my life in hours
I serve you by expiring
I vanish faster when I am thin
and slower when I am thick
The wind is my energy
What am I?

What kind of band never plays music?