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 52 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?

The U.S. Pharmacopeia Medication Errors Reporting Program states that approximately 50% of all medication errors involve insulin.

Did you know?

Approximately 500,000 babies are born each year in the United States to teenage mothers.

Did you know?

For high blood pressure (hypertension), a new class of drug, called a vasopeptidase blocker (inhibitor), has been developed. It decreases blood pressure by simultaneously dilating the peripheral arteries and increasing the body's loss of salt.

Did you know?

Blastomycosis is often misdiagnosed, resulting in tragic outcomes. It is caused by a fungus living in moist soil, in wooded areas of the United States and Canada. If inhaled, the fungus can cause mild breathing problems that may worsen and cause serious illness and even death.

Did you know?

Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.

For a complete list of videos, visit our video library