Research this week will be done over the Respiratory system
List the major organs
Explain the functions of the Respiratory system
Which other systems does the Respiratory system work with?

might need to ask questions people no or have read somthing about.

answer is b,

"the tracer looks harmless in flight, but the pilot’s bitten lips and white knuckles suggest how dangerous it can be."

it was correct.

following gollum to the back entrance

sentence lenght varies according to word choice.you select which word to use and that will require to use other expressions that collocate with the word chosen.sentence length will vary   according to the choice of words you make to express your ideas.