askable

1 :  fit or proper to be asked … a question that Wordsworth took to be altogether askable, and which, indeed, he spent eighty-five lines answering—the question what happiness really is—soon looked to philosophers under Bentham's influence like a question whose answer was so obvious that it could not be asked in earnest. — Martha C. Nussbaum, Daedalus, 22 Mar. 2004

2 :  approachable and capable of being asked a question I think it is important that you be an askable parent, so that he will know that he can come to you with any sort of question and that you'll give him a straight answer. — Ruth Westheimer, Chicago Tribune, 14 Dec. 1995