Write a java program which defines unconstrained array of user defined length n (the value of n is to be taken from a proper user’s input). fill in the array with n random numbers. the application should (1) display all elements of the array, (2) display the sum of all elements, and (3) calculate the average of all elements.
random numbers need to be generated inside the program making use of the prebuilt java random numbers generator available in the math library class.

Assignment: permutations use the permutation formula   r ! ! n n p nr   to solve each problem. be sure to show all work leading to your answer. part i: solve real-world permutation problems choose any four (4) of the following five problems to solve. for each problem a) show how the permutation formula can be used to find the answer and b) write a sentence to explain the meaning of the answer for the situation. 1. to register for online banking services at a local credit union, you need to select a four-digit personal identification number, or pin code. the digits cannot be repeated. how many ways are there to arrange four digits out of the numerals 0 through 9 to create a code?