# 3i Infotech Papers: Sample Questions 626 - 628 of 1245

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## Question number: 626

MCQ▾

### Question

1. `void main ()`
2. `{`
3. `    float j;`
4. `    j = 1000 * 1000;`
5. `    printf ( “%f”, j);`
6. `}`

### Choices

Choice (4) Response

a.

Error

b.

Overflow

c.

1000000.000000

d.

All of the above

c.

### Explanation

In the program

 float j; Define the float variable j j = 1000 * 1000; Here j = 1000 * 1000 = 1000000 printf (“%f”, j); Print the value if j = 1000000.000000

## Question number: 627

Essay Question▾

### Describe in Detail

What is Relational Calculus?

### Explanation

• Relational calculus is an query language which is non procedural, and instead of algebra it uses mathematical predicate calculus.

• The relational calculus is not the same like that of differential and integral calculus in mathematics, but takes its name from a branch of symbolic logic termed as predicate calculus.

• When applied to databases, it is found in two forms. These are

• Tuple relational calculus which was originally proposed by Codd in the year 1972 and

• Domain relational calculus which was proposed by Lacroix and Pirotte in the year 1977

## Question number: 628

Essay Question▾

### Describe in Detail

What is a concrete class?

### Explanation

• A concrete class defines useful object that can be instantiated as an automatic variable on the program stack.

• The implementation of a concrete class is defined.

• It is not intended to be a base class.

• Concrete is the default type of class such class can have direct instances.

• A derived class that implements all the missing functionality is the concrete class in inheritance.