Blood Relations

A1, A2, A3, A4, A5, A6, A7, A8, A9 and A10 are ten members of the same family. There are three couples out of the ten persons in the family. The persons are related to each other as:
I. A7 is the brother-in-law of A9 and has one unmarried sister-in-law
II. A6 is the grandmother of A10.
III. A5 has one nephew and two nieces.
IV. A10 is the only cousin of A4.
V. A1 is married and has one sister-in-law.
VI. A8 is the sister of one person and the daughter of another person among the given people.
VII. A9 is son of A2. He is married and has one son and no daughter.

1, The gender of how many persons can be uniquely determined?

2. How many of the following statements is/are true?
I. A1 has two daughters
II. A5 has two brothers
III. A2 has two grand-daughters
IV. A7 has two nieces

3. How many of the following statements is/are true?
I. A1 has two daughters
II. A5 has two brothers
III. A2 has two grand-daughters
IV. A7 has two nieces