This is a computer program, why is there an error between the computer average and the nominal values of r?

Jason works as an accountant in a department store. he needs to keep a daily record of all the invoices issued by the store. which file naming convention would him the most?

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)?

Helen is having a meeting with her colleagues in her company. they are working on the goals and objectives for the coming year. they want to ensure that these goals and objectives of the processes involved are properly evaluated. which system can helen and her colleagues apply to evaluate this? helen and her colleagues require a blank to evaluate the goals and objectives.