You want to place a piece of glass tubing into a rubber stopper after the tubing has been fire polished and cooled. this is best done by

When you attempt to place a piece of glass tubing into a rubber stopper after the tubing has been fire polished and cooled, you should do D. All of the above.

When inserting a piece of glass tubing that has been fire polished and cooled into a rubber stopper, you should ensure that you:

In conclusion, all of the above are necessary when inserting a piece of glass tubing into a rubber stopper.

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Options for this question include:

A. lubricating the tubing with water or glycerin.

B. using a towel or cotton gloves for protection.

C. twisting the tubing and stopper carefully.

D. all of the above

not only is it colder, it also becomes darker, less salty, and more dense.

ya the other dude is right