Questions

First, Dr.Will wear both of the gloves, one above the other. He operate the first person. After finishing he remove the outer pair of gloves as inside out and place it in a tray. Then operate the second person. Now he will wear the first gloves as inside out above the second gloves. Operate the third person. At last he remove the gloves and dispose them.

The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being bent (refracted) by the liquid core.

There are two types of Shadow zones:

one for P waves and

one for S waves.

P wave shadows between 104-140 degree, both sides; S wave shadow from 105 of one side to 105 of the other.

Snow Leopard

You will get the answer in the riddle itself, if you read the riddle carefully.

The riddle says "A cowboy arrives in town on Friday." So Friday is the name of the horse on which he comes. Hence, the only possibility is he arrives on the horse friday on Tuesday, stays for 3 days and leaves on the same horse on Friday.