Question

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
lubricating the tubing with water or glycerin.
using a towel or cotton gloves for protection
twisting the tubing and stopper carefully.
all of the above.
other:
approved eye protection devices (such as goggles) are worn in the laboratory
to avoid eye strain.
to improve your vision
only if you dont have corrective glasses.
any time chemicals, heat or glassware are used. 4. if you wear contact lenses in the school laboratory.
other

Explanation:

For the first question:

• Lubricating the tubing with water or glycerin reduces friction.
• Using a towel or cotton gloves protects hands from cuts.
• Twisting the tubing and stopper carefully ensures proper insertion. So all steps are correct.

For the second question:

• Approved eye - protection devices (like goggles) are worn any time chemicals, heat or glassware are used in the laboratory for safety. Eye strain and vision improvement are not the main reasons. And they are not only for those without corrective glasses.

Answer:

For the first question: all of the above.
For the second question: any time chemicals, heat or glassware are used.