Answer:
Option no 3
Explanation:
Metallic elements aren't usually crumbled in normal air pressure and conditions.
Answer:

Explanation:
It is given that,
The radius of the inflated balloon is 7 cm.
We need to find the volume of air inside the balloon in milliliters.
The balloon is in the shape of a sphere whose volume is given by :

Hence, the volume of the air inside the balloon is
.
<u>Answer:</u> The correct answer is Option D.
<u>Explanation:</u>
Atomic mass of an atom is defined as the sum of number of neutrons and number of protons that are present in an atom. It is represented as 'A'.
Atomic number = Number of protons + Number of neutrons
We are given:
Number of protons = 6
Number of neutrons = 6
Number of electrons = 6
Atomic mass = 6 + 6 = 12
Hence, the correct answer is Option D.