Question Discussion & Solution

The correct answer is 18 Groups and 7 Periods.

• Modern Periodic Table has 18 Groups and 7 Periods.
• It has 118 Elements.
• Each of the tables has a vertical row is called groups. Elements in groups have similar chemical and physical properties because they have the same number of outer electrons.
• Each of the tables has horizontal rows is called periods. During a period, a gradual change in chemical properties occurs from one element to another.
• It was given by Dmitri Mendeleev.
• The Structure of it is like a bird Grid.
• The Modern Periodic table is used to organize all the known elements.
• Advantages of Modern Periodic Table:- 
  •  It is easier to remember the properties of an element if its position in the periodic table is known.
  • It made the study of Chemistry Systematic and Easy.

Modern Periodic Table:-

Concept:

A functional dependency is a constraint between two sets of attributes from the database.

Explanation:

In general form, a functional dependency denoted by X -> Y between two sets of attributes X and Y that are subsets of R specifies a constraint on the possible tuples that can form a relation state r of R.

The constraint is that for any two tuples T₁ and T₂ in r that have T₁[X] = T₂[Y], they must also have T₁[Y]

= T₂[Y]. It means that values of Y component of a tuple in r depend on or are determined by the value of X component.

If a relation R contains attributes (X and Y). Then X -> Y is a functional dependency. It means X functionally determines Y in R if and only if two tuples agree on their X value, they must necessarily agree on their Y value.

The correct answer is Sodium carbonate.

Key Points

• A toothpaste is defined as a semi-solid material for removing naturally occurring deposits from teeth and is supposed to be used simultaneously with a toothbrush.
• Toothpaste generally contains the following components:
  • Water (20–40%)
  • Abrasives (50%) including aluminum hydroxide, calcium hydrogen phosphates, calcium carbonate, magnesium carbonate, silica, and hydroxyapatite.
  • Fluoride (usually 1450 ppm) mainly in the form of sodium fluoride.

The correct answer is Vitamin B1.

Key Points

• When rice is produced and not polished it is called brown rice. 
• Brown rice is rich in Vitamin B1. 
• When brown rice is polished, rice loses many vitamins and minerals including Vitamin B1 through the bran.
• Vitamin B1 also called thiamine is an essential vitamin, a deficiency of which is known to cause beriberi.

Additional Information

In this question we shows that Pen is used for Writing.

Similarly, Spoon is used for Eating.

But Gun comes under Weapon, Teacher teach in School and Eraser and Pencil is different things.

Option 1, 3 and 4 is not correct.

Hence, "Spoon : Eating" is the correct answer.