Questions

Covalent bonds hold atoms together because the attraction between the positively charged nuclei and the negatively charged shared electrons is greater than the repulsions between the nuclei themselves.

Here in this declaration public static void main string[] args, each keyword has its importance.

1. public - Here public is an access specifier which allows the main method to be accessible everywhere.

2. static - static helps the main method to get loaded without getting called by any instance/object.

3. void - void clarifies that the main method will not return any value.

4. main - It's the name of the method.

5. String[] args - Here we are defining a String array to pass arguments at the command line. args is the variable name of the String array.

National Hockey League game is divide into 3 Periods each of 20 minutes. During the regular season, if the game ends in a tie, a 5 minute, sudden death overtime is played. In the playoffs, the overtime is 20 minutes long.

3+2×55=113

(or)

3+2×10=23

In chemistry, the term transition metal has three possible meanings: The IUPAC definition defines a transition metal as "an element whose atom has a partially filled d sub-shell, or which can give rise to cations with an incomplete d sub-shell".

Any of the set of metallic elements occupying a central block (Groups IVB–VIII, IB, and IIB, or 4–12) in the periodic table, e.g. iron, manganese, chromium, and copper. Chemically they show variable valency and a strong tendency to form coordination compounds, and many of their compounds are coloured.

Here in the given options, only iron (Fe) is a transition metal since Strontium is an alkaline earth, arsenic is a metalloid, hydrogen is (normally) a diatomic gas.

We know that, there are 7 continents in the world. They are :

Asia, Africa, Australia, North America, South America, Europe and Antarctica.

Africa - 53 countries

Asia - 48 countries

Europe - 45 countries

Antarctica - 0 countries

Hence, the continent Africa has most number of countries with 53 countries and in second place Asia has 48 , third Europe has 45 countries.