Here is a set of basic questions producing integer or string outputs. Answer them and format the result precisely with the JSON instructions provided:

Question 0 (Question id: q_t4r9dD):
Solve for q: 9*q + 18 = 27 Respond with an integer.

Question 1 (Question id: q_jIPn24):
Calculate 2 + 4.



Produce a JSON object whose top-level keys are the question ids.

Each key’s value must be an object holding an 'answer' field.
If the response to a question is an integer that is even, add the field 'additional_answer_info' containing 'half_answer' (answer ÷ 2) and 'double_answer' (answer × 2).
If the response to a question is a string, add a 'first_char' field containing its first character.

Now provide the result JSON using the described format.

{"ground_truth": {"q_t4r9dD": {"answer": 1}, "q_jIPn24": {"answer": 6, "additional_answer_info": {"half_answer": 3, "double_answer": 12}}}}