Our; Green; in; but; sleep; stop
Answer:
2,4,3,1
Explanation:
he created a successful artificial part, then aims to create another one thats superior, he rebuilts his limbs for the experiment (goal) and learns to walk with the part(artificial limbs)
No context to properly answer question
The most credible source in terms of researching the effects of smoking is letter b, research article in a scientific journal. It is because a credible source means that it is valid or could be relied on in which the research article is, because it has been researched and holds validity of which contains proof. Other choices does not correspond to the question for they don't hold any validity or proof in the topic that could be reliable.