What goes up but never comes down?

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

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.

What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

How is a fly different from a mosquito?

Complete the given grid with valid words. You can only use the letters AAEEIIMMPPTT.

Hint: The grid reads the same across as down.

My location can be determined by the below rebus.
So where am i ?