Vector Space with inner product

Question

I would appriciate your help with the question below :

V is a vector space with inner product.

A = {a1,...,ak}   B = {b1,...,bk}  such that :

<ai , bj> = {1 , i = j
            {0 , i != j         for  1 <= i,j <= k

I want to know if spB = (spA)⊥

(⊥ is a sign for euclidean vector space , such that every vector in the subspace is orthogonal to every vector in the complement)