1. For each of the following strings, write "yes" or "no" depending on whether the string is a legal names of a Java variable.; if your answer is "no", briefly explain why.
September5 yes
5September no: does not start with a letter
September 5 no: has a blank space inside
September_5 yes
September$ yes (but not recommended)
2. Translate the following sequence of Java statements into English; show, step by step, what will happen after each of these statements.
double grade;
declare a new variable of type double;
its name is grade, its value is undefined
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| ? |
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grade
grade = 3.0;
to the variable grade, we assign a value 3.0
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| 3.0 |
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grade
grade = grade + 1.0;
we add 1.0 to the previous value of the variable grade, and assign the
result to the same variable
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| 4.0 |
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grade
3. What is the result of the following Java operations:9 / 5 the result is 1
9.0 / 5.0 the result is 1.8
9 % 5 the result is 4
-9 % 5 the result is -4