QUESTION 18 In AbstractSet class, which method retums the intersection of two sets? O a. or Ob. and intersect Od. sub QUESTION 19 Suppose my dict is a Dictionary object. Which AbstractDict method is...

Extracted text: QUESTION 18 In AbstractSet class, which method retums the intersection of two sets? O a. or Ob. and intersect Od. sub QUESTION 19 Suppose my dict is a Dictionary object. Which AbstractDict method is called in the following operation? my_dict[x] = 20 O a_update O b. add getitem O d. setitem In a tree, which of the following is true? O a. each item can have multiple children O b. the root has exactly one parent Oc all items have a distinct predecessor and successoT O d. each item can have multiple parents QUESTION 15 Which of the following is the topmost node in a tree and does not have a parent? O a. interior node O b. child O C. root O d. leaf QUESTION 16 Which of the following is true about a binary tree? O a. each node has at most two children O b. each node has only one child O c. the root node must have only one chhid O d. child nodes can have multiple parents