Answer:
15.) The value of the variable areaRect after the above statements have been executed is 70.0.
The first statement assigns the value of 7.0 to the variable 1en. The second statement assigns the value of 10.0 to the variable width.
Finally, the third statement multiplies the value of 1en with the value of width and assigns the result to the variable areaRect.
So areaRect = 1en * width = 7.0 * 10.0 = 70.0
16.) The value of the variable slope after the above statements have been executed is 0.75.
The first two statements assigns the values of 3.0 and 5.0 to the variables x1 and y1 respectively.
The second two statements assigns the values of 10.0 and 8.0 to the variables x2 and y2 respectively.
Finally, the last statement calculates the slope of the line defined by the points (x1,y1) and (x2,y2) using the formula: (y2 - y1) / (x2 - x1) and assigns the value to the variable slope.
So slope = (y2 - y1) / (x2 - x1) = (8 - 5) / (10 - 3) = 3/7 = 0.75
It's worth noting that in the equation given, there is no parenthesis around (y2 - y1) and (x2 - x1) which gives the wrong result, so the correct format should be:
slope = (y2 - y1) / (x2 - x1);
17.) The value of the variable slope after the above statements have been executed is 0.1.
The first two statements assigns the values of 2.0 and 7.0 to the variables x1 and y1 respectively.
The second two statements assigns the values of 12.0 and 9.0 to the variables x2 and y2 respectively.
Finally, the last statement calculates the slope of the line defined by the points (x1,y1) and (x2,y2) using the formula: (y2 - y1) / (x2 - x1) and assigns the value to the variable slope.
in this case, slope = (y2 - y1) / (x2 - x1) = (9-7)/(12-2) = 2/10 = 0.1
18.) The expression 4 + 3.0 is a double.
In this expression, 4 is an integer, and 3.0 is a double. In most programming languages, when you perform an operation involving an integer and a double, the result will be a double.
19). The expression 3.0 + 4.0 is a double.
Both 3.0 and 4.0 are double and when they are added the result is also double.
20.) The expression 4 % 3 is an int.
21.) The expression 5 / 3 is an int.
The / operator performs division. In most programming languages, when you divide two integers, the result will also be an integer, and any remainder is truncated. So, 5 divided by 3 will give 1 as the quotient and 2 as the remainder. The expression 5 / 3 evaluates to 1 which is an integer.
22.) The expression 15.0 / 3 is double.
In this expression 15.0 is a double and 3 is an integer. When we divide a double by an integer, the result will be a double. So, 15.0/3 will give 5.0 as the result. The expression 15.0 / 3 evaluates to 5.0 which is a double.
23.) The expression 17 % 5 is int.
The % operator performs modulo operation which returns the remainder of the division of left operand by the right operand. In most programming languages, when you use the modulo operator with two integers, the result will also be an integer. So, 17 % 5 will give 2 as the remainder. The expression 17 % 5 evaluates to 2 which is an integer.
24.)
- sum = sum + 1;
- sum += 1;
- sum++;
All of these three ways will add 1 to the int variable sum. The first way uses the addition operator (+) and the assignment operator (=) to add 1 to sum. The second way uses the shorthand operator (+=) to add 1 to sum. The third way uses the increment operator (++) to add 1 to sum.
25.)
The first rule for creating a user identifier is that it must start with a letter or an underscore (_).
The second rule is that it can only contain letters, digits, and underscores.
The third rule is that it should not be a keyword or a pre-defined identifier of the programming language you are using.
Note that different programming languages may have different rules for naming conventions, but these are the general rules.
26.) correct