Sentence 1. The subject is variety and it requires the singular verb is.
Sentence 2. The subject is range and it also requires the singular verb is.
The English language allows for a large numbers of interrupters (prepositional phrases, relative clauses, appositives, etc.) to be placed between the simple subject and its verb, but they still have to agree in number and person. Try reducing the sentence to its basic meaning: variety is available and range is offered.
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