Each of the following sentences has one mistake .Circle and correct the mistakes

Each of the following sentences has one mistake .Circle and correct the mistakes.
1 How (A)many (B)floors(C)does his house(D)has ?
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2 (A)Pop music (B)are popular with(C) young people(D)all over the woorld
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3 They(A)did these exercises (B)good and (C)their teacher gave (D)them hight maks
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4(A)The boy and the girl (B)was(C)happy (D) because they were given gifts
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5(A)How (B)are you(C)going(D)getting to the airport ?
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