def calc_default_resistance_coeffs(test_mass, regression_curves):
    """
    Approximating typical P_resistance based on vehicle test-mass.

    The regression-curves are in the model `resistance_coeffs_regression_curves`.
    Use it for rough results if you are missing the real vehicle data.
    """
    a = regression_curves
    f0 = a[0][0] * test_mass + a[0][1]
    f1 = a[1][0] * test_mass + a[1][1]
    f2 = a[2][0] * test_mass + a[2][1]

    return (f0, f1, f2)