Assume that mortality is described by de Moivre's law with the maximum age, $=110$ and

the force of interest, $=0\mathrm{.}05.$ An individual aged $(20)$ purchases a $20-$year endowment

insurance with a death benefit of RM$150,000$ payable at the moment of death. Meanwhile, the

individual will receive $RM50,000$ if the individual survives until $20$ years after the policy

issued. Calculate the net single premium for this insurance policy.