= 4. (AMLCR) 6.18. A life is subject to extra risk that is modelled by a constant addition to the force of mortality, so that, if the extra risk functions are denoted by's M' = Mix +0. Show that at rate of interest i, L = (z); + plz)j, where j is a rate of interest that you should specify. = 4. (AMLCR) 6.18. A life is subject to extra risk that is modelled by a constant addition to the force of mortality, so that, if the extra risk functions are denoted by's M' = Mix +0. Show that at rate of interest i, L = (z); + plz)j, where j is a rate of interest that you should specify