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_a9ncOI9):
How many times does the letter "b" appear in the text: "they but duly"? Respond with an integer.

Question 1 (Question id: q_zpmOta91):
Solve for a: 155 - 8*a = 131 Respond with an integer.

Question 2 (Question id: q_G7lD3V2I):
Calculate ( -4 + -1 * -5 ).



Return a JSON with each question id as a key.

The value for each key should be an object that contains the answer in the field 'answer'. Additionally, if the task is about counting legs of animals or counting letters in a string, add the task_type field with value 'leg_counting' or 'letter_counting', respectively.
If the response to a question is an integer that is even, also add the field 'half_answer' to the object which contains the answer integer divided by two.
For string answers, include 'first_char' with the answer’s initial letter.
If the question asks for the last character of a string, add an 'original_string' field containing the source string.

Now provide the result JSON using the described format.

{"ground_truth": {"q_a9ncOI9": {"answer": 1, "task_type": "letter_counting"}, "q_zpmOta91": {"answer": 3}, "q_G7lD3V2I": {"answer": 1}}}