please help me to solve these questions correctly and asap.

Question 2 The playing life of a brand A radio, X, is normally distributed with mean of 600 hours and standard deviation of 100 hours. (i) Calculate the probability that playing life of the radio is between 400 to 700 hours. (4 marks) (ii) Calculate the probability that playing life of the radio is at most 700 hours. (4 marks) (ii) Find the number of hours below which 10% of the playing life lies. (4 marks) CS Chuupona In c Cameinanner