Answer:
40g
Explanation:
Solubility of Copper sulfate at 90°=60g
Solubility of potassium bromide at 90°=100g
100g-60g=40g
This is a comet. It is also called a dirty snowballs.
Gravitational force is determined by mass
Answer: Option B
<u>Explanation:</u>
According to Universal law of gravity, the gravitational force is directly proportional to the product of the masses of the objects and inversely proportional to the square of the distance between the objects.

Where,
G – gravitational constant = 
= masses of two objects
r – distance between the objects
So, as per this law, the gravitational force is found by mass.
surface wave is a wave that travels along the surface of a medium. The medium is the matter through which the wave travels. Ocean waves are the best-known examples of surface waves. They travel on the surface of the water between the ocean and the air.
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