I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

I am thinking of a five-digit number such that:
The first and last digits are the same, their submission is an even number and multiplication is an odd number and is equal to the fourth number. Subtract five from it and we obtain the second number. Then divide into exact halves and we get the 3rd number.

What number I am thinking of?

Which point will the car reach to go out?

Which Number is the odd one out?

A) 7145
B) 2716
C) 5321
D) 4135

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

What work can one never finish?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.

Count the number of times the letter "F" appears in the following paragraph:

FAY FRIED FIFTY POUNDS OF
SALTED FISH AND THREE POUNDS
OF DRY FENNEL FOR DINNER FOR
FORTY MEMBERS OF HER FATHER'S FAMILY.

John went to meet his friend Jacob, but when he was about to reach the main gate, John notices that Jacob had a mighty dog who was fastened to the tree. The chain is long enough that it allows the dog to reach the main gate.

How can the John reach the main gate?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?