Answers

Two rules of logical operator are as follows. i) The output of the logical AND operation is TRUE if Both the logical expressions are individually TRUE. ii) The output of the logical OR operation is TRUE if either or the logical expressions is TRUE.

The joining of two or more strings is called concatenation of string. The string are connected by the string operators which is the plus sign (+).

Logical Operators combine two or more relational expressions to evaluate a single value as True (Non Zero) or False (Zero). The result of evaluation is used to make decisions about the program flow. The commonly used logical operators in QBASIC are AND, OR and NOT. It's any two types are as follows: a)AND b) OR

Relational  Operator are used to compare to values two values of some type either both numeric or both string. A comparison of sting data with numeric data cannot be done. The comparison of sting data is done on the basis of ASCII value. The result of comparison is either true (non zero) or false (zero). Two example of relational operator are < and >.

Arithmetic  operator are used for various mathematical calculation . Arithmetic operators performed such as addition, subtraction, multiplication, division and exponentiation. A numeric expression is any collection of operators and operands. Two example of arithmetic operators are + and -.

Keywords are specific words that are reserved as programming language commands. This words may only be used for their intended purpose some of the keywords of QBASIC programming are REM, INPUT, PRINT etc.