13 [TURN OVER CST.2004.3.4 5 Operating Systems II (a) What problem do real-time scheduling algorithms try to solve? [12 marks] (b) Describe one static priority and one dynamic priority real-time scheduling algorithm. You should discuss the issue of admission control, and comment on the data structures that an implementation would need to maintain and on how these would be used to make scheduling decisions.are a data structure protected by a mutual exclusion lock. (i) What scheduling problem could arise here? [2 marks] (ii) How could this problem be overcome? [2 marks] (d) The designer also wishes the real-time system to use demand paged virtual memory for efficiency. 3a. Submit this table. At the minimum, the table (or a screenshot of the table) must contain the ticker (tic), company name (conm), percentages of observations with 4 in the first digit after the decimal, and percentages of observations with 5 in the first digit after the decimal. How do I create the table? - WHAT TO INCLUDE: In this program, you will write program to use a symbol table, in other words, an application program. You are not implementing a symbol table ADT. Your program will declare a variable of type BST and use that as explained below. Notes and frequenciesEvery musical note has a note name and a frequency. You are given a file where each line contains a note name (string), a tab character, and a frequency (double). For example, here are the first few lines from the file notes_frequencies.txt: A0 27.5 A#029.13513 B0 30.86177 C1 32.7032 C#1 34.64179 D1 36.7081 D#1 38.89091 E1 41.20135 F1 43.6536 These can be stored in a symbol table with the note name as the key and the frequency as the value. A chord is several notes played simultaneously. So a chord can then be represented in a text file where each line contains two or note names separated by a space: a duration in seconds (double) and a note name (string). For example, the file chords.txt would contain: C3 E3 G3 C4 D#4 G4 C5 E5 G#5 C16 D#6 F#6 C3 E3 G3 B13 C5 D#5 G5 B5 C6 E6 G6 A#61.Requirements-First, place both data files into your Eclipse data folder. Then, a program called PlayChords that: prints your name followed by three asterisks;reads the lines in the file data/notes_frequencies.txt line by line, splitting each line into a note name and a frequency, and placing that note/frequency into a symbol table class (e.g., BS1T) where the note is the key and the frequency the value; reads the lines in the file data/chords.txt line by line and, for each:splits each line into an array of Strings;declares an array of type Double; for each entry in the String array, looks up the frequency of that note in the symbol table and places the frequency into the corresponding position in the Double array calls the playChord method (see below) with the Double array; Insert this method into your program. public static void playChord(double... frequencies) { final int sliceCount = (int) (StdAudio.SAMPLE_RATE * 0.5); final double[] slices = new double[sliceCount+1]; for (int i = 10; i <= sliceCount; i++) { for (double frequency: frequencies) { slices[i] += Math.sin(2 * Math.PI * i * frequency / StdAudio.SAMPLE_RATE); } slices[i] /= frequencies.length; } StdAudio.play(slices); } You will need to import algs4.StdAudio.Grading rubric. The program is worth 24 points, broken down as follows: 12 for putting your name at the top of the program and printing it in your output 12 for declaring the symbol table object correctly 2 for specifying the first input file pathname correctly 3 for correctly reading the first file line by line 2 for splitting the line correctly 2 for adding to the symbol table correctly 2 for specifying the second input file pathname correctly 13 for correctly reading the second file line by line 12 for splitting the line correctly 11 for retrieving the frequency correctly 12 for filling the frequency array correctly 1 for playing the frequency correctly User Analysis: You must have a clear view of the users of this system. Consider that not everyone is comfortable with the technology. For example, you need to deal with user variation such as age or language skills. Task Analysis: to identify the tasks the potential users will perform, and in what order.Heuristic Evaluation: Consolidate your findings from your user and task analysis and propose a design and specify system requirements to realize the recommended interface. For example, the number of items to display, the screen size, what colours, how many different screens to display, the devices to you, the physical design. Low-Fidelity Prototype: Develop a low-fidelity (paper) prototype (a minimum of 4 screens). Based on the above requirements, develop a prelimmary design of the user interface. At this stage, the prototype is basically a medium to support your initial concept and ideas.