Explanation

Carbon-12 (12C) is the most abundant of the two stable isotopes of carbon (carbon-13 being the other), amounting to 98.93% of element carbon on Earth;

its abundance is due to the triple-alpha process by which it is created in stars.

Explanation

In the year 1913, Niels Bohr proposed an atomic structure model,

describing an atom as a small, positively charged nucleus

Explanation

He was unfit for the job

وہ اس کام کے لیے نااہل تھا۔

unfit for use means: not suitable or good enough for a particular purpose or activity

Explanation

Synonyms of signify (verb mean, indicate)

SIgnify اشارہ کرنا

Indicate اشاره کرنا

Explanation

the finger is to the elbow as the toe is to the knee.

Reason: the finger is the end point of the elbow,

similarly, the toe is the end point of the knee.

Explanation

Uranium-235 is used in nuclear power plants for power generation.

 The uranium is processed into small ceramic pellets and stacked together into sealed metal tubes called fuel rods.

Explanation

The products of combustion include:

hydrogen gas,

carbon dioxide,

water vapor,

heat and light.

Explanation

In moving down to the halogen group E.N. decreases hence Iodine has the lowest electronegativity.

DETAIL ANSWER:

 iodine has the lowest electronegativity.

Fluorine has the highest electronegativity followed by chlorine and bromine,

and then with the least reactivity, we have iodine, among the given options.

Hence, option D is correct.

Note: The noble gases i.e. group 18 elements have no electronegativity.

Explanation

Electric current is the flow of electrons in a conductor.

The force required to make current flow through a conductor is called voltage and potential is the other term of voltage.

Explanation

presentation software includes:

Visme,

Haiku Deck,

Prezi,

Microsoft Powerpoint