Question

a.
4. Which of the following methods is used
to increase friction?
Lubrication b. Polishing
c. Increasing roughness
d. Reducing roughness
5. Which of the following is used to decrease​

Answer 1

Answer:

Option c is ur correct answer.

Explanation:

$Increasing \: roughness \: increase \: friction.$

Answer 2

Answer:

option c is also correct