The function main double main(); a. Declares a function called main which takes an integer as an argument and returns a double. b. Defines a function called double which calculates squareroot s. c. Defines a function called main which takes no argument and returns a double. d. Declares a function called main which takes a double as an argument and returns an integer. A variable that can have values only in the range 0 to 65535 is a: a. Four-byte int. b. Four-byte unsigned int. c. Two-byte int. d. Two-byte unsigned int. Two variables in one declaration are separated by what symbol? a. Dot. b. Comma. Parentheses. d. Braces. What is wrong with the following while loop? while (sum