What is the word or phrase?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

I look at you, you look at me I raise my right, you raise your left. What am I?

What do you see in the image below

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

Living above a star, I do not burn
Eleven friends and they do not turn
I can just be visited in a sequence, not once or repeatedly
PQRS are my initials
Can you tell my name accurately?

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?

A woman named Maria was at the funeral of her mother. She met a nice young man that she had never seen before and after the service, they spent a bit of time together. Then she got busy and didn’t get his name or phone number before he left. She tried to find him, but no one knew who he was or how to contact him. A few weeks later, Maria’s older sister dies and the police suspect murder. Who killed the sister?

What Deficiency does the below rebus represent?

VIT_MIN