The Ricker scale, as well as other measurement, (has, have) been used to record the magnitude of earthquakes. Subject verb agreement

Which is these is not a benefit of parallel structure? a)clarity b)classification c)emphasis d)balance

What event shows how eckels' character develops over the course of the story sound of thunder

Which would best develop a well-organized and logical research paper? a. narrow goals b. a variety of sources c. good research results d. a strong topic