Grammar question pls help its a test. its__ one thousand note.(a, an, the). they__ already finished the work (have, had)​

When evaluating the relevance of a source he plans to use, marco needs to consider a. the author's use of connotation and figurative language. b. the balance between words and visuals. c. whether the authorship of the source is specified. d. whether it's too general or too specialized for his intended audience.

How do i avoiding writing run-on sentences?

What is the number of main idea? i need this answer .