Scored C/P #4 and typo in #7?

[doctor.octopus]

Hello,

For question 7, it refers to "Experiment 2" but no experiment is listed in the passage. wtf???? (see attached image for this question).

The only information is the passage is about Sn1 and Sn2 reactions. But it doesn't give any indication of whether it's asking about Sn1 or Sn2 and there's no mention of any experiments at all.

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For number 4 :
I didn't understand this question. "What is NOT true about the dehydration of malic acid to fumaric and maleic acid?"

-rxn occurs most readily with tertiary alcohols
-involves loss of a water molecule
-involves a carbocation
-rxn is stereospecific

I understand why the answer is the last option -- obviously it can't be stereospecific if both cis and trans isomers are formed.

But why is the first option true? Malic acid isn't a tertiary alcohol....

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[Cytarabine]

O Chem was 7 years ago, but that reaction looks like a dehydration, no?

 

[aldol16]

If the reaction is talking about SN1 and SN2, then this looks like an acid-catalyzed nucleophilic substitution where the acid just protonates the alcohol to turn it into an excellent leaving group.

For the other one, does the reaction proceed through an E1 mechanism?

 

[doctor.octopus]

For #7, yes, the answers show various possibilities with E1 or Sn1 and you select the one without a hydride shift. My question was about how to interpret what the question is asking, since the passage never talked about an "experiment"... Was wondering if this was a typo, or if I was missing something.

For #4, I understand that dehydration reactions are faster with tertiary alcohols because they make a better LG when protonated. I was again wondering about interpreting the questions and answers.

Since it's asking specifically about what's NOT true of the dehydration SPECIFICALLY of those species, which are NOT tertiary alcohols, the fact that "better with tertiary R-OH" would be considered "true" was confusing to me. It's not asking about dehydration in general, see?

I was just wondering if y'all could just shed some light on the thought process behind looking at these questions/answers.