A material that is commonly used as a solid lubricant is:
a. tallow, graphite, molybdate sulfide, mica, and polymer films
b. graphite, soapstone, molybdenum disulphide, mica, and polymer films
c. lime, sodium carbonate, molybdate sulfide, mica, and polymer films
d. lime, graphite, molybdenum disulphide, tallow, and polymer films
e. graphite, soapstone, molybdate sulfide, mica, and polymer films
Answer: B