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

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

I go up and I go down.
I go up towards the beautiful sky and down toward the green ground.
I am present tense.
I am past tense too
Children love me.

Who Am I?

Count the number of squares in the picture below.

We have four gears with below features=> Both Gear A and D has 60 teeth=> Gear B has 40 teeth=> Gear C has 20 teeth=> Every two minutes, Gear B makes 25 full turns.What is the relative speed of Gear A and Gear B?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Can it be possible to build a house that has all its four walls facing towards the South?

What goes through cities and fields, but never moves?

Solve the following series:
AZ, GT, MN, __, YB