1.12. A life annuity of $6000 per annum, payable monthly in advance with a deferment period of 10 years, is purchased for a life aged 50 by a single premium. Based on a 6% annual rate of interest,

a) obtain the single premium

b) obtain the single premium under the condition it is returned without interest at the end of the year of death, if death occurs before the age of 60.