What word begins and ends with an E, but has only one letter?

I know a nine-letter word having only one vowel.
Do you ?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Those who excel at picture puzzles to find hidden objects often possess keen attention to detail, high IQ, and the ability to process visual information at lightning speed.

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

You are provided with a grid (as shown in the picture). Can you fill the squares with numbers 1-8 in a manner that none of the two consecutive numbers are placed next to each other in any direction (vertically, horizontally or diagonally?)

You walk into a room and see a bed. On the bed, there are two dogs, five cats, a giraffe, six cows, and a goose. There are also three doves flying above the bed. How many legs are on the floor?

I make two people out of one. What am I?