Detailed solution please

[7] 2. Computer Science student Doom Kopf has written an app that will randomly generate guitar Riffs in a selected key. Each Riff has length which is nmnlally distributed with mean length 8 seconds and standard deviation 2 seconds. To accompany popular rap artist BB. Gun's latest hit single Hotter than Haggis, the program selects 22 riffs at random. [3] 3.. Find the probability that this random selection of 22 Riffs will have total length of more than 3 minutes. [4] h. Hotter than Haggis lasts a total of 360 seconds {including time required for the exploding hag- pipes]. How man},r Rie need to be selected to obtain the expected length of 361] seconds and What is the probability that their total length is between 350 and 3T0 seconds