Identify the hidden meaning behind this picture?

Solve the puzzle by telling what does below picture means.

Can you find out the remainder when 3^300 is divided by 5?

What does a man do only once in his lifetime, but women do once a year after they are 29?

Solve The below Equation:

ALFA + BETA + GAMA = DELTA

People are waiting in line to board a 100-seat aeroplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it's available, otherwise, they will choose an open seat at random to sit in. The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat?

What does this mathematical rebus means ?

Which Travels Faster? Solve below famous picture riddle:

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?

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?