A set of rules which defines the ways in which words can be coupled in sentences is called:
Correct Answer: B
Syntax is the branch of linguistics that studies the structure and rules of sentences in natural languages. Lexis is the vocabulary of a language. Semantics is the study of meaning in language. A dictionary is a collection of words and their definitions, synonyms, pronunciations, etc. Reference: [Python Institute - Entry-Level Python Programmer Certification]
Question 22
What is the expected result of the following code?
Correct Answer: A
Explanation The code snippet that you have sent is trying to use the global keyword to access and modify a global variable inside a function. The code is as follows: speed = 10 def velocity(): global speed speed = speed + 10 return speed print(velocity()) The code starts with creating a global variable called "speed" and assigning it the value 10. A global variable is a variable that is defined outside any function and can be accessed by any part of the code. Then, the code defines a function called "velocity" that takes no parameters and returns the value of "speed" after adding 10 to it. Inside the function, the code uses the global keyword to declare that it wants to use the global variable "speed", not a local one. A local variable is a variable that is defined inside a function and can only be accessed by that function. The global keyword allows the function to modify the global variable, not just read it. Then, the code adds 10 to the value of "speed" and returns it. Finally, the code calls the function "velocity" and prints the result. However, the code has a problem. The problem is that the code uses the global keyword inside the function, but not outside. The global keyword is only needed when you want to modify a global variable inside a function, not when you want to create or access it outside a function. If you use the global keyword outside a function, you will get a SyntaxError exception, which is an error that occurs when the code does not follow the rules of the Python language. The code does not handle the exception, and therefore it will terminate with an error message. The expected result of the code is an unhandled exception, because the code uses the global keyword incorrectly. Therefore, the correct answer is A. The code is erroneous and cannot be run.
Question 23
What is true about exceptions and debugging? (Select two answers.)
Correct Answer: A,C
Explanation Exceptions and debugging are two important concepts in Python programming that are related to handling and preventing errors. Exceptions are errors that occur when the code cannot be executed properly, such as syntax errors, type errors, index errors, etc. Debugging is the process of finding and fixing errors in the code, using various tools and techniques. Some of the facts about exceptions and debugging are: A tool that allows you to precisely trace program execution is called a debugger. A debugger is a program that can run another program step by step, inspect the values of variables, set breakpoints, evaluate expressions, etc. A debugger can help you find the source and cause of an error, and test possible solutions. Python has a built-in debugger module called pdb, which can be used from the command line or within the code. There are also other third-party debuggers available for Python, such as PyCharm, Visual Studio Code, etc12 If some Python code is executed without errors, this does not prove that there are no errors in it. It only means that the code did not encounter any exceptions that would stop the execution. However, the code may still have logical errors, which are errors that cause the code to produce incorrect or unexpected results. For example, if you write a function that is supposed to calculate the area of a circle, but you use the wrong formula, the code may run without errors, but it will give you the wrong answer. Logical errors are harder to detect and debug than syntax or runtime errors, because they do not generate any error messages. You have to test the code with different inputs and outputs, and compare them with the expected results34 One try-except block may contain more than one except branch. A try-except block is a way of handling exceptions in Python, by using the keywords try and except. The try block contains the code that may raise an exception, and the except block contains the code that will execute if an exception occurs. You can have multiple except blocks for different types of exceptions, or for different actions to take. For example, you can write a try-except block like this: try: # some code that may raise an exception except ValueError: # handle the ValueError exception except ZeroDivisionError: # handle the ZeroDivisionError exception except: # handle any other exception This way, you can customize the error handling for different situations, and provide more informative messages or alternative solutions5 The default (anonymous) except branch can be the last branch in the try-except block. The default except branch is the one that does not specify any exception type, and it will catch any exception that is not handled by the previous except branches. The default except branch can be the last branch in the try-except block, but it cannot be the first or the only branch. For example, you can write a try-except block like this: try: # some code that may raise an exception except ValueError: # handle the ValueError exception except: # handle any other exception This is a valid try-except block, and the default except branch will be the last branch. However, you cannot write a try-except block like this: try: # some code that may raise an exception except: # handle any exception This is an invalid try-except block, because the default except branch is the only branch, and it will catch all exceptions, even those that are not errors, such as KeyboardInterrupt or SystemExit. This is considered a bad practice, because it may hide or ignore important exceptions that should be handled differently or propagated further. Therefore, you should always specify the exception types that you want to handle, and use the default except branch only as a last resort5 Therefore, the correct answers are A. A tool that allows you to precisely trace program execution is called a debugger. and C. One try-except block may contain more than one except branch.
Question 24
Drag and drop the code boxes in order to build a program which prints Unavailable to the screen. (Note: one code box will not be used.)
Correct Answer:
Question 25
Insert the code boxes in the correct positions in order to build a line of code which asks the user for a float value and assigns it to the mass variable. (Note: some code boxes will not be used.)
Correct Answer:
Explanation One possible way to insert the code boxes in the correct positions in order to build a line of code that asks the user for a float value and assigns it to the mass variable is: mass = float(input("Enter the mass: This line of code uses the input function to prompt the user for a string value, and then uses the float function to convert that string value into a floating-point number. The result is then assigned to the variable mass. You can find more information about the input and float functions in Python in the following references: [Python input() Function] [Python float() Function]
