function setHeightQuestion(){
        var first_question_block = $('#b_survey').find('.answer_block').filter(':first').height()+40;
        $('#b_survey').height(first_question_block);
}

function switchQuestion(){
	var questionId = 0;
	$('.next_btn').click(function(){
	    var answer_blocks = $('#b_survey').find('.answer_block');
	    answer_blocks.each(function(){
	        answer_blocks.hide();
	    });

	    var this_id = $(this).attr('id');
        var next_block = $('#r'+this_id).next();
        var next_block_height = (next_block.height()+40);

        $('#b_survey').height(next_block_height);

	    next_block.show();
	})
}