What was the key invention that enabled computers to go in every home and office

Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate for the data below. internet speed levels of "fast comma " "medium comma " and "slow" choose the correct answer below. a. the ordinal level of measurement is most appropriate because the data can be ordered comma but differences left parenthesis obtained by subtraction right parenthesis cannot be found or are meaningless. nothing nothing nothing nothing nothing b. the interval level of measurement is most appropriate because the data can be ordered comma differences left parenthesis obtained by subtraction right parenthesis can be found and are meaningful comma and there is no natural starting point. c. the nominal level of measurement is most appropriate because the data cannot be ordered. nothing d. the ratio level of measurement is most appropriate because the data can be ordered comma differences left parenthesis obtained by subtraction right parenthesis can be found and are meaningful comma and there is a natural starting point.

For a typical middle-income family, what is the estimated cost of raising a child to the age of 18? $145,500 $245,340 $304,340 $455,500

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)?