Could someone please help me with this trigonometric problem?:(

What can be said about the relationship between triangles and circles? check all that apply. a) many circles can be inscribed in a given triangle b) exactly one triangle can be inscribed in a given circle c) exactly one circle can be inscribed in a given triangle d) many triangular shapes can be circumscribed about a given circle

Cam bought some used books for $4.95. he paid $0.50 each for some books and $0.35 each for the others. he bought fewer than 8 books at each price. how many books did cam buy?

In a small section of a stadium there are 40 spectators watching a game between the cook islands and fiji. they all support at least one of the two teams. 25 spectators support the cook islands and 16 of these support both teams. how many support only fiji?