Which statement about the characteristics of floating-point number data types is false? a. Floating-point numbers include a decimal point and at least one number after the decimal point. b. Floating-point numbers can be positive or negative. c. Floating-point numbers can be expressed in decimal notation or E notation. d. Floating-point numbers are stored in conventional binary format or E notation. When concatenating variables, the best practice is to a. concatenate integers first before strings b. avoid using the + operator c. use a new variable for the concatenated string d. place quotation marks around the variable names Why are primitive data types useful to programmers? a. They allow more control because programmers can specify how to manipulate a primitive data type and where to store it. b. They save time because programmers only tell the programming language what to do with the primitive data type, not how do it. c. They are the simplest variable type available and do not require any functions to manipulate the associated data. d. They are not built into your programming language but can be constructed as desired from composite data types