Question 1:
The correct usage of parenthetical documentation is:
A Numerous experiments had been attempted, but "the results were wildly inconclusive" (Johnson 20).
This response correctly places the citation at the end of the quote and correctly uses punctuation.
Question 2:
The proper citation for the Works Cited page is:
C Johnson, Kevin. THE CRUCIAL EXPERIMENTS ON ANTIMATTER. New York: Wilson and Low, 1989.
This format adheres to the correct MLA style for citing a book, listing the author's name first, followed by the title, publication location, publisher, and year of publication, all in the correct order.