? 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', u's = pz+. Show that at rate of interest i, A = (z); + (z)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', u's = pz+. Show that at rate of interest i, A = (z); + (z)j, where j is a rate of interest that you should specify. ==