A well designed and configured security guard at the door allowing only authorized personnel into the building. a) Network Adapter b) Antivirus Software c) Intrusion Detection System d) Firewall

Eye injuries usually occur as a result of all of the following things, except: a) proper machine operation b) battery explosion c) falling or flying debris d) electric welding arc

When creating a budget, log fixed expenses before income. after income. after savings. at the top.

Suppose there is a relation r(a, b, c) with a b+-tree index with search keys (a, b).1. what is the worst-case cost of finding records satisfying 10 < a < 50 using this index, in terms of the number of records n1, retrieved and the height h of the tree? 2. what is the worst-case cost of finding records satisfying 10 < a < 50 and 5 < b < 10 using this index, in terms of the number of records n2 that satisfy this selection, as well as n1 and h defined above? 3. under what conditions on n1 and n2, would the index be an efficient way of finding records satisfying the condition from part (2)?