How can we tell the computer what to put on the web page, and how to organize it?

Consider the transactions shown in Table 7.14, with an item taxonomy given in Figure 7.25.

(a) What are the main challenges of mining association rules with item
taxonomy?
(b) Consider the approach where each transaction t is replaced by an ex-
tended transaction t'
that contains all the items in t as well as their re-
spective ancestors. For example, the transaction t = { Chips, Cookies}
will be replaced by t'
= {Chips, Cookies, Snack Food, Food}. Use this
approach to derive all frequent itemsets (up to size 4) with support ?
70%.
(c) Consider an alternative approach where the frequent itemsets are gen-
erated one level at a time. Initially, all the frequent itemsets involving
items at the highest level of the hierarchy are generated. Next, we use
the frequent itemsets discovered at the higher level of the hierarchy to
generate candidate itemsets involving items at the lower levels of the hi-
erarchy. For example, we generate the candidate itemset {Chips, Diet
Soda} only if {Snack Food, Soda} is frequent. Use this ap

Assume int[] t = {1, 2, 3, 4}. What is t.length?

a. 0 b. 3 c. 4 d. 5