Adigital communication link carries binary-coded words representing samples of an input signalxa(t) = 3 cos(600πt) + 2 cos(1800πt).the link is operated at 10,000 bits/s and each input sample is quantized into 1024 different voltage levels. a) what are the sampling frequency and the folding frequency? b) what is the nyquist rate for the signal xa(t)? c) what are the frequencies in the resulting discrete-time signal x[n]? d) what is the resolution?

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? a)give the file a unique name b)name the file in yymmdd format c)use descriptive name while naming the files d)use capital letters while naming the file

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)?

What is a programming method that provides for interactive modules to a website?