How do you go from 98 to 720 using just one letter?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

A bomb exploded in a room full of married couples and no one died. How?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?

There were three women in all the swimming costumes!
One was happy and the other two were sad!
The happy one was crying and the sad ones were smiling.
Why was this?

It spends most of its day eating white, but when it’s quick enough, it gets to eat fruit and sometimes some blue things. It’s in a dark room, where the walls are blue, it runs from a ghost that roams the halls and haunts it all the time. What is it?

While preparing the table for dinner, wife came up with an idea to tease his mathematician husband. She asked her husband to pick nine toothpicks and make ten without breaking any toothpick.

The husband was also smart and did it within seconds. How ?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?