2018 SRSS P2

This question paper consists of 7 printed pages and 1 blank page. Name__________________________________ ( ) Class: Sec _________ SERANGOON SECONDARY SCHOOL PRELIMINARY EXAMINATION 2018 SECONDARY 4 EXPRESS COMPUTING 7155/02 PAPER 2 28 Aug 2018 Name of Setter: 2 hour 30 minutes READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue or black pen. Answer all questions. All tasks must be done in the computer laboratory. Programs are to be written in Python. A Quick Reference Glossary for Python is provided. The number of marks is given in brackets [ ] at the end of each question or part question. Retrieve the template files from the COMPEXAM folder in the thumb drive. Save your work inside the COMPEXAM folder in the thumb drive using the file name given in the question as and when necessary. FOR EXAMINER’S 50

2 Quick Reference for Python This quick reference shows some examples of the Python language constructs. The complete Python language is not limited to these examples. 1. Identifiers When naming functions, variables and modules, the following rules must be observed: Names should begin with character 'a' - 'z' or 'A' - 'Z' or '_' and followed by alphanumeric characters or '_' Reserved words should not be used. User-defined identifiers are case sensitive. 2. Comments and Documentation Strings # This is a comment """ This is a documentation string over multiple lines """ 3. Input/Output print ("This is a string") s = input ("Instructions to prompt for data entry.") 4. Import import <module> e.g. import math 5. Data Type Data Type Notes int integer float real number Bool boolean str string (immutable) list series of values 6. Assignment Assignment Statement Notes a = 1 integer b = c variable d = "This is a string" string mylist = [1, 2, 3, 5, 5] list or array 7. Arithmetic Operators: Operator Notes + - plus, subtract * / multiply, divide % remainder or modulus ** exponential or power // quotient of floor division 8. Relational Operators: Operator Notes == equality != not equal to > >= greater than, greater than or equal to < <= less than, less than or equal to 9. Boolean Expression Boolean Expression Notes a and b logical and a or b logical or not a logical not 10. Iteration while loop for loop while condition(s): <statement(s) for in range(n): <statement(s)> for record in records: <statement(s)>

3 11. Selection Type 1 Type 2 Type 3 if condition(s): <statement(s)> if condition(s): <statement(s)> else: <statement(s)> if condition(s): <statement(s)> elif condition(s): <statement(s)> else: <statement(s)> 12. Built-in functions (a) Basic functions abs( ) chr() float() input() int() ord( ) print( ) range( ) round( ) str( ) format( ) (b) Mathematical functions ceil( ) exp() fabs() floor() log() max( ) min( ) pow( ) sqrt( ) trunc( ) format( ) (c) String functions endswith( ) find() isalnum() isalpha() digit() islower( ) isspace( ) isupper( ) len( ) lower( ) startswith( ) upper( ) 13. Reserved Words Reserved words cannot be used as identifiers. They are part of the syntax of the language. False None True and as assert break class continue def del elif else except finally for from global if import in is lambda nonlocal not

4 Task 1 A sports event organiser uses a spreadsheet to record the height and weight of the participants. You are required to finish setting up the spreadsheet to record the health risk of the participants. Open the file BMI. You will see the following data. Some of the rows in the file have been hidden in the display below so you can see the top and bottom. Save the file as BMI_PART<class _name>_<index no>_<your name> 1. In cell B26 enter a formula to count how many participants are there in the event. [1] 2. In cell B27 enter a formula to count calculate the average age of the participants. [1] 3. In cell B28 enter a formula to calculate the age range of the participants. [1] 4. The formula to calculate BMI is given as BMI = kg / m2 where kg is the weight (in kg) and m2 is the square of the height in metres. Use the formula to complete the BMI column. Round these values to one decimal place. [3] 5. Use an appropriate function to search for the Health Risk in the BMI Range table and use it to complete the Risk column. [2] 6. 6 Use a conditional statement, to identify those participants who are at risk. Put a YES in the Healthy column if the participant has a healthy weight. Otherwise put NO in the Healthy column and format the cells with a NO to automatically show a red background. [2] Save and close your file.

5 Task 2 The following program accepts the age for 20 people and prints out the average age. total=0 ppl=20 for i in range(ppl): age = int(input("Enter age : ")) total = total + age average = total/ppl print("Average age is ", average) Open the file AGE.py Save the file as PAGE_<class _name>_<index no>_<your name>. 7. Edit the program so that it: (a) Accepts age for 50 people. [1] (b) Prints out the number of people whose age are below 18 years old. [4] (c) Tests if the age input is between 15 to 65 (inclusive), and if not, asks the user for input again as necessary. [3] Save your program. 8. Save your program as VARAGE_<class _name>_<index no>_<your name>. Edit your program so that it works for any number of people. [2] Save your program.

6 Task 3 The following program should check who can become a GRAB driver using the following rules: • age at least twenty-one years old • minimum two years of driving experience • hold a valid Private Hire Car Driver’s Vocational License (PDVL) • Singapore citizen The program calculates the number of people who qualify to be a GRAB driver and the number rejected. The program finishes when an age of zero is input. The number of people who qualify to be GRAB driver and the number rejected are then printed out. There are several syntax and logical error(s) in the program. age = 0 exp = 0 pdvl = "N" citizen = "N" rejected = 0 age = int(input("Please enter your age " )) exp = int(input("Please enter years of driving experience " )) pdvl = input("Do you hold a Private Hire Car Driver Vocational License (PDVL): (Y/N) ") citizen = int(input("Are you a Singapore Citizen (Y/N) ")) while age == 0: if age < 21 or exp > 2 or pdvl == "N" or citizen == "N": if age <= 21: print("You are too young to drive") if exp < 2: print("You do not have enough driving experience") if pdvl == "N": print("You need to obtain a PDVL license first") else citizen == "N": print("You have to be a Singapore Citizen") rejected -= 1 elif: print("You qualify to be a GRAB driver ") qualify = qualify + 1 age = int(input("Please enter your age " )) exp = int(input("Please enter years of driving experience ")) pdvl = input("Do you hold a Private Hire Car Driver Vocational License (PDVL): (Y/N) ") print("Number of people rejected ", qualify) print("Number of people qualified ", qualify) Open the file GRAB.py Save the file as GRAB_<class _name>_<index no>_<your name> 9. Identify and correct the errors in the program so that it works correctly according to the rules above. Save your program. [10]

7 Task 4 You have been asked to write a program to calculate the average three-day temperature in Singapore. The daily temperature reading is taken at four different locations in Singapore. The program should allow you to: • Enter data in the format n, s, e, w where n, s, e, w indicates the temperature reading at four locations in Singapore. An example 29.7, 30.5, 31.6, 29.5 • Only allow data entry of one decimal pl