please explain the ans clearly, thanks

(a) Are the following statements true or false? Briefly explain your answer. i) The duration of a zero-coupon bond equals its time to maturity. ii) Holding maturity constant, a bond's duration is lower when the coupon rate is higher. iii) Holding other factors constant, the duration of a coupon bond is higher when the bond's yield to maturity is lower. (12 marks) (b) It is not possible to forecast stock returns in an efficient market. (4 marks)