Answer: the answer is B
Explanation: by stating that with tablets, people read 30% slower, it means that book reader is better than reading online, so that is the author's claim.
The past perfect refers to a time earlier than before now. It is used to make it clear that one event happened before another in the past. It does not matter which event is mentioned first - the tense makes it clear which one happened first.
The answer is unsettle
Meaning for establish: <span>set up on a firm or permanent basis.
Hope this helps:))
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