def _set_default_capacitance(
    subcategory_id: int,
    style_id: int,
) -> float:
    """Set the default value of the capacitance.

    :param subcategory_id:
    :param style_id:
    :return: _capacitance
    :rtype: float
    :raises: KeyError if passed a subcategory ID outside the bounds.
    :raises: IndexError if passed a style ID outside the bounds when subcategory ID
        is equal to three.
    """
    _capacitance = {
        1: 0.15e-6,
        2: 0.061e-6,
        3: [0.027e-6, 0.033e-6],
        4: 0.14e-6,
        5: 0.33e-6,
        6: 0.14e-6,
        7: 300e-12,
        8: 160e-12,
        9: 30e-12,
        10: 3300e-12,
        11: 81e-12,
        12: 1e-6,
        13: 20e-6,
        14: 1700e-6,
        15: 1600e-6,
        16: 0.0,
        17: 0.0,
        18: 0.0,
        19: 0.0,
    }[subcategory_id]

    if subcategory_id == 3:
        _capacitance = _capacitance[style_id - 1]

    return _capacitance