Answer:
Gravity or the gravitational force is defined as the force of attraction occurring between all states of matter. The sun’s gravity, mass, and radius plays a crucial role in the properties of the Sun.
Explanation:
The gravity of an object can be determined using the formula:

Now, according to the question, the mass of the sun is halved, which will be written as:

Thus, according to the equation, the mass of an object is directly proportional to the gravitational field. since, the mass of the Sun is reduced to half, the gravity of the Sun will be halved.
Answer:
Option C= A hydrogen bond formed between a polar side chain and a hydrophobic side chain.
Explanation:
All three given options a, b and d have common mechanism to accommodate the polar amino acid.
A= A hydrogen bond forms between two polar side chains.
B= A hydrogen bond from between a polar side chain and protein back bone.
D = hydrogen bond form between polar side chains and a buried water molecules.
All these are use to accommodate the polar amino acid.
While option C is not used. which is:
A hydrogen bond formed between a polar side chain and a hydrophobic side chain.
Answer:
A.The sound becomes louder.
And
C.The sound waves get further.
Explanation:
Louder the sound it will travel long.