求下列集合的基数：(1) A = (r_1, r_2, ..., r_n, r, r, ...) : r, r_i in mathbb{Q) : i = 1, 2, ..., n; n = 1, 2, ...};(2) B = (varepsilon_1, varepsilon_2, ..., varepsilon_n, ...) : varepsilon_i in {0, 1, i = 1, 2, ...};(3) C = mathbb(Q)^infty = (r_1, r_2, ..., r_n, ...) : r_i in mathbb{Q), i = 1, 2, ...}.

求下列集合的基数：

(1) $A = \{(r_1, r_2, \cdots, r_n, r, r, \cdots) : r, r_i \in \mathbb{Q} : i = 1, 2, \cdots, n; n = 1, 2, \cdots\}$;

(2) $B = \{(\varepsilon_1, \varepsilon_2, \cdots, \varepsilon_n, \cdots) : \varepsilon_i \in \{0, 1\}, i = 1, 2, \cdots\}$;

(3) $C = \mathbb{Q}^{\infty} = \{(r_1, r_2, \cdots, r_n, \cdots) : r_i \in \mathbb{Q}, i = 1, 2, \cdots\}$.