You can use child observation and assessment to a. find areas of your classroom environment you can improve. b. determine areas where you may need professional development. c. support learning and instruction, as well as identify children who may need additional services. d. identify whether your curriculum is working or not.

The answer is C 

Some connecting rods have to lubricate the cylinder wall or piston pin. the answer is letter d. graphite coating can be a major  additive to many  coating  systems and things such as connecting rods.  it functions as a refractory, lubricant, thermal conductor, and electrical conductor for a machine or thing to enhance its work.