chapter 10 week 6 quiz

chapter 10 week 6 quiz

Quiz

 

1. What is the difference between a Python tuple and Python list?
   
   1.   Lists are mutable and tuples are not mutable
   2.   Lists are indexed by integers and tuples are indexed by strings
   3.   Lists maintain the order of the items and tuples do not maintain order
   4.   Tuples can be expanded after they are created and lists cannot
2. Which of the following methods work both in Python lists and Python tuples?
   
   1.   sort()
   2.   append()
   3.   pop()
   4.   index()
3. What will end up in the variable y after this code is executed?
   x , y = 3, 4
   1.   A two item list
   2.   A dictionary with the key 3 mapped to the value 4
   3.   A two item tuple
   4.   4
4. In the following Python code, what will end up in the variable y?
   x = { 'chuck' : 1 , 'fred' : 42, 'jan': 100}
   y = x.items()
   1.   A list of strings
   2.   A tuple with three integers
   3.   A list of tuples
   4.   A list of integers
5. Which of the following tuples is greater than x in the following Python sequence?
   x = (5, 1, 3)
   if ??? > x :
   ...
   1.   (4, 100, 200)
   2.   (0, 1000, 2000)
   3.   (6, 0, 0)
   4.   (5, 0, 300)
6. What does the following Python code accomplish, assuming the c is a non-empty dictionary?
   tmp = list()
   for k, v in c.items() :
   tmp.append( (v, k) )
   1.   It computes the largest of all of the values in the dictionary
   2.   It sorts the dictionary based on its key values
   3.   It creates a list of tuples where each tuple is a value, key pair
   4.   It computes the average of all of the values in the dictionary
7. If the variable data is a Python list, how do we sort it in reverse order?
   
   1.   data = sortrev(data)
   2.   data = data.sort(-1)
   3.   data.sort.reverse()
   4.   data.sort(reverse=True)
8. Using the following tuple, how would you print 'Wed'?
   days = ('Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun')
   1.   print(days[1])
   2.   print(days(2))
   3.   print(days.get(1,-1))
   4.   print(days[2])
9. In the following Python loop, why are there two iteration variables (k and v)?
   c = {'a':10, 'b':1, 'c':22}
   for k, v in c.items() :
   ...
   1.   Because the keys for the dictionary are strings
   2.   Because there are two items in the dictionary
   3.   Because the items() method in dictionaries returns a list of tuples
   4.   Because for each item we want the previous and current key
10. Given that Python lists and Python tuples are quite similar - when might you prefer to use a tuple over a list?
    
    1.   For a temporary variable that you will use and discard without modifying
    2.   For a list of items that want to use strings as key values instead of integers
    3.   For a list of items that will be extended as new items are found
    4.   For a list of items you intend to sort in place