We defined the operation of concatenation for sets of strings on page 10 in the textbook as: ab = {xy | x element a and y element b} are the regular sets closed under concatenation? in other words, if a and b are regular sets, is ab guaranteed to be a regular set? prove or show a counterexample.

How many pairs of chromosomes do human body cells contain?

Your program will make use of long long int variables for all calculations. note: the use of long long int requires that you have c++11 support. you should have this automatically if you are using a newer version of visual studio. the support is there for gcc as well, but you may need the -std=c++11 or -std=c++0x compiler flag. you first need to read in the total number of seconds. there is no prompt for the read (that is, you just do the cin without using a cout to display a prompt). this is going to seem a little strange when you are running your program in your ide

When running anti-virus software , what could be a reason where recipitent is not guaranteed that data being streamed will not get interrupted?