This topic contains a solution. Click here to go to the answer

Author Question: The oil in a vacuum pump should be changed _____. a. about every five minutes of pump operation ... (Read 133 times)

SGallaher96

  • Hero Member
  • *****
  • Posts: 509
The oil in a vacuum pump should be changed _____.
 
  a. about every five minutes of pump operation
  b. only when changing from one refrigerant to another
  c. immediately after pumping down a wet or contaminated system
  d. about every 25 hours of pump operation

Question 2

It is important to clean dross and carbon deposits from a cut surface before welding because they can _____.
 
  a. produce extremely hazardous fumes during welding
  b. form hard, brittle zones and porosity in the weld zone
  c. damage certain welding equipment components
  d. cause molten metal to be blown considerable distances



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Zebsrer

  • Sr. Member
  • ****
  • Posts: 284
Answer to Question 1

c

Answer to Question 2

b




Zebsrer

  • Sr. Member
  • ****
  • Posts: 284

 

Did you know?

There are immediate benefits of chiropractic adjustments that are visible via magnetic resonance imaging (MRI). It shows that spinal manipulation therapy is effective in decreasing pain and increasing the gaps between the vertebrae, reducing pressure that leads to pain.

Did you know?

Though “Krazy Glue” or “Super Glue” has the ability to seal small wounds, it is not recommended for this purpose since it contains many substances that should not enter the body through the skin, and may be harmful.

Did you know?

There are actually 60 minerals, 16 vitamins, 12 essential amino acids, and three essential fatty acids that your body needs every day.

Did you know?

In most climates, 8 to 10 glasses of water per day is recommended for adults. The best indicator for adequate fluid intake is frequent, clear urination.

Did you know?

Most women experience menopause in their 50s. However, in 1994, an Italian woman gave birth to a baby boy when she was 61 years old.

For a complete list of videos, visit our video library