For each kilogram of a carbon–oxygen composition (30%612C) that is burned to produce iron, 7.3×1013 J of energy is released. Assuming an initial 1.38M⊙ white dwarf with a radius of 1600 km, how much iron would have to be produced to cause the star to be gravitationally unbound? How much additional iron would have to be manufactured to produce a Type Ia supernova with an average ejecta speed of 5000 km s−1? Take the gravitational potential energy to be −5.1×1043 J for a realistic white dwarf model, and express your answers in units of M⊙.