R, how to find the number of rows in an object? Please use the which statement

Please help with Java code. Create student class  Name  Id  Marks    Create array of 10 student and print all students

What occurs when using the ref or out keyword with an array parameter?

Assume an array is defined as int[] nums = {7, 15, 23, 5};. Which of the following would place the values in the array in descending numeric order?   a. Array.Reverse(nums);     b. Array.Reverse(nums); Array.Sort(nums);     c. Array.Sort(nums);     d. Array.Sort(nums); Array.Reverse(nums);

What value does a Random object use in the absence of a seed value?\

In Python, grades_dict = {'Wally': [87,96,70], 'Eva': [100,87,90], 'Sam': [94,77,90], 'Katie': [100,81,82],                'Bob': [83, 65, 85]} Ask user to enter the names of the rows, i.e., indices. You can use: len(grades) to get the number of rows of the DataFrame. In addition, using the sort_index() method, ask user whether they wish to sort by rows or by columns and whether to sort in ascending or descending order (do not use any if-else statements)

JAVA column average /*for example, if table has: 123456789 Your method should return: 4.0, 5.0, 6.0

Describe how to make an array of struct elements.

2DArray method:It will allocate a block of memory which represents a two-dimension arraybased on the input values supplied by the user. Ask the user to enter the number of rows andcolumn for 2D array that the user want to manipulate. The number of rows and columns that theuser enters may or may not define a square matrix (when the number of rows equals the numberof columns). The array will have exactly rows time columns (m * n) elements. It will notcontain any extra or empty cells. Initialize the “matrix” by rows with random number between 1to 100. Pass two arguments by out reference so that you can assign the number of row andcolumns of data to the first and second arguments. This is return 2D array method afterallocating new memory for 2D array and initialize it with random value. Generate randomnumber code in C# as following: Random randnum = new Random( );int number = randnum.Next (1, 101);SwapRow method: it will rotate the data in the matrix in an up/down method such that the…

What value does a Random object use in the absence of a seed value?\