Which of the following is NOT one of the four benefits of using email?

Which of the following is a way the operating system prevents unknown or unauthorized users from accessing the system?

The word ‘play’ comes with many different interpretations and a variety of definitions. discuss some of the various meanings tied to the word play. why is the concept of play thought to be an important addition to the workplace? do some (brief) research online and give an example of how play in the workplace is being done right.

Write a method named addall that could be placed inside the hashintset class. this method accepts another hashintset as a parameter and adds all elements from that set into the current set, if they are not already present. for example, if a set s1 contains [1, 2, 3] and another set s2 contains [1, 7, 3, 9], the call of s1.addall(s2); would change s1 to store [1, 2, 3, 7, 9] in some order. you are allowed to call methods on your set and/or the other set. do not modify the set passed in. this method should run in o(n) time where n is the number of elements in the parameter set passed in.