Instance variables are often called ____ to help distinguish them from other variables you might use.

Which of the following is not a rule that must be followed when naming identifiers?

a. After the first character, you may use the letters a-z, A-Z, an underscore, a dollar sign, or the digits 0-9. b. Identifiers can contain spaces. c. Uppercase and lowercase characters are distinct. d. The first character must be one of the letters a-z, A-Z, an underscore, or a dollar sign.

If you want to sort your database . . .

a. Must select entire database b. None of the others c. Just click anywhere in the column by which you want to sort. d. Just click entire column by which you want to sort