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1. What does this program print? ``

python
class Node:
    def __init__(self, value, next=None):
        self.value = value
        self.next = next

c = Node(3)
b = Node(2, c)
a = Node(1, b)
a.next = c
print(a.value, a.next.value)
print(b.value, b.next.value)

``

1 2 2 31 3 2 None1 3 2 31 3 3 3

2. What does this program print? ``

python
grid = [[1, 1], [2, 2]]
shallow = grid.copy()
shallow[0][0] = 9
shallow[1] = [5, 5]
print('grid =', grid)
print('shallow =', shallow)

``

grid = [[1, 1], [2, 2]] shallow = [[9, 1], [5, 5]]grid = [[9, 1], [2, 2]] shallow = [[9, 1], [5, 5]]grid = [[9, 1], [2, 2]] shallow = [[9, 1], [2, 2]]grid = [[9, 1], [5, 5]] shallow = [[9, 1], [5, 5]]

3. What does this program print? ``

python
base = ['x', 'y']
view = base
snapshot = tuple(base)
base[0] = 'q'
print(view, snapshot)

``

['x', 'y'] ('x', 'y')['x', 'y'] ('q', 'y')['q', 'y'] ('q', 'y')['q', 'y'] ('x', 'y')

4. In a picture of references, what does a.next = x change?

It moves only the arrow that leaves a's next field, so it now points at x, and both nodes stay where they areIt moves the box for x so that it sits right after the box for aIt copies the node a and gives the copy the value of xIt moves the box for a so that it sits next to the box for x

5. What does this program print? ``

python
a = [1, 2, 3]
b = a
print(a is b)

``

False, because b = a made a second list with the same valuesTrue, because is compares the values inside the two listsTrue, because both names lead to the same list objectFalse, because is never works on lists

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