21. The main components of a computer's hardware are: a. Central Processing Unit (CPU) b. Main Memory Secondary Memory / Storage All of the above le: 22. The command is used to display information on the conso a. print b. cin c cout 23. which of the following is used as a preprocessor directive: a. using namespace std; b. Comments at the top of the code int mainO include 24. You use the keyword to read input from the keyboard: a print b, cin c. cout d. write 25. If you want to manually convert a data type to double, you use theword: ConvertO b.) static_ cast e. DoubleO d. None of the above 26. Formatting the output for numeric and string data controls which of the following: a. size b. position c. d. Number of digits All of the above 27. Which of these satisfies the relational expression x > 10 to evaluate to true: a. x=2 b, x=10 d) x = 12 28. Floating point data types use how many bytes of memory? a. 2 bytes b. 4 bytes c. d. 8 bytes None of the above 29. Software Engineers use a number of tools including the following: a. b. Program specifications Charts and diagrams c. Pseudocode d. All of the above