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

Considering the below equation:

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?

In the image below, can you find the value of an angle(y)

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

What is the word or phrase?

In an office's desk, you find a unique method that shows the current day of the month. Two numbered cubes are used to depict the current date.

Can you find out the numbers on both the cubes so that each date can be mentioned using them?

Please note that you have to use both the cubes to display any date. Thus the 1st day must be represented by 01 and so on.

Can anyone tell me a word in the English dictionary which has a silent 'z'?

In the given picture, you can find two letters missing. When two particular letters are placed in the missing spots, you get an eight-letter word while reading in the anti-clockwise direction. Can you find out the missing letters and the missing word eventually?

Can you find out the total number of triangles in the given figure?