If two's company, and three's a crowd, then whats four and five ?

In the following picture, E is going to slide the object down and as per the terrain and the physics, the round object is going to travel all the way till the end. Now, can you analyze who all people will die when it happens?

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?

The answer I give is yes, but what I mean is no. What was the question?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

The dirtier I get, the whiter I look. Who am I?

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

Give it food and it will live; give it water and it will die.

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?