Choose the tag pairs that are used in a description list.

Which of the following protocols is used to send time synchronization updates on a given network?

A. NTP B. POP3 C. DNS D. IMAP

Convert the following mathematics expressions to C++ expressions. Use the declarations provided. Indicate the appropriate header file for any library function used. Be sure you initialize any variables whose values you are using to reasonable values for the library functions you are using.

``` int x, y; //declaration for a) and b) a) y = x 3 b) y <= |x| double x, y, z, area; //declaration for c) through e). c) z = x 1.6 d) z = area area e) p =xy xy ```