Yes. Liquid nitrogen (below -196 deg C) is quite an effective steriliser.
Boiling cannot sterilize scissors but heating at temperatures above the boiling point of water in an autoclaving (121oC) would sterilize scissors after 15-20 minutes.
They are used for very cold temperatures.
When you want to pasteurize foods and to sterilize food containers, flatware, dishes.
UV light radiation kills bacteria and can sterilize utensils (UV rays are used to sterilize goggles in the laboratory, for example.
Yes, endotoxins are heat stable and can withstand high temperatures. This is one reason why autoclaving is often used to sterilize equipment and media in laboratories to remove endotoxins.
steam
To sterilize instruments.
Decreases are often represented by negative numbers. Temperatures outside of most tropical regions are occasionally negative on the commonly used scales.
Yes, the mean can be negative if the numbers being averaged are negative. For example, if you are averaging temperatures and all of the temperatures are below zero, your average temperature will be a negative number.
gamma rays
handpiece should be sterilize after using on each patient.
Sterility can be achieved with filtration as filtration will allow the positive bacteria to sift through, while the negative harmful bacteria will be pulled out and separated from the organism as it once was.