Please help me with 1,2,3,4 please

1) C. simile

2) Dangerous          Polluted         Pleasant

        Yes                       No                       No

3) C. tornados pose challenges for scientists

4) However, Scientists decided the experiment was as unsafe as a leaky boat and dropped the project.

Explanation:

1) A simile compares two diffrent things and uses words such as "like" or "as".

2) They didn't go on with the experiment because it was too dangerous, which is the opposite of pleasant.

3)  A and B can't be because it was dangerous and hard to study it, since TOTO failed and was too dangerous, I don't think they'll be trying teh same thing next time. D is also incorrect because it is dangerous to stand in front of a tornado and not fun. That only leaves C which is what the text describes.

4) They use a simile again using "as" to compare the safety of the experiment to a leaky boat.  

c. explains words’ origins and variations.

yes, elmers glue is non toxic. i called them a couple months and asked the same question. they said it was