for Q2 it can be solved by normal distribution function here sigma =2 MU=0 put in the equation answer will be 1
for Q3 it will be solved by gamma Function method https://study.com/academy/lesson/gamma-function-properties-examples.html
https://www.youtube.com/watch?v=tp0HiqJPh_E
for Q1 my approach is lengthy unable to get the answer
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