Calculate the value today of a security that promises the future expected cash flows beginning in year 1, assuming a discount rate of 10%.a) $80 for the first years 1-3, followed by $150 for the following 5 years . b) Growth rate in cash flows of 10% pa in perpetuity. Cash flow in year 0 was $80.c) As with b) only assume that the growth rate is 12%d) As with b) only assume that the growth rate is negative 2%. Does this make economic sense? e) As with b) only assume that the present value is $1,680 and the growth rate is unknown. What is the growth rate?