For this case you must first know the definition of density.
D = m / v
where,
m: mass
v: volume.
You can then write the following hypothesis:
IF you know two physical characteristics of an object then you can determine the density. First weigh the object, THEN measure its volume BECAUSE the density is the quotient between the mass and the volume of an object.
The answer is the first one. That's because the general theory of relativity is the thing experiencing whatever is experiencing relative to something else. The second answer is just plain wrong. The third answer is just a constant, and doesn't relate to experiencing anything. And the fourth answer is a force between two objects, and it has no second comparison. The first answer is how a subject experiences two different things.
The speed of light is determined by the medium (material) through which the light is travelling. Light travels faster in a vacuum than it does in any other medium. Light changes speed as it passes from one medium to another. This is called refraction.
Answer:
18%
Explanation:
There are two equal and opposite forces on a floating object: weight and buoyancy.
W = B
The weight of an object is its mass times gravity: W = mg
Buoyancy is the weight of the displaced fluid: W = mf g
Plugging in:
mg = mf g
m = mf
Mass is density times volume:
ρV = ρf Vf
Solving for the ratio of Vf / V:
Vf / V = ρ / ρf
Given that ρ = 0.82 g/mL and ρf = 1.00 g/mL:
Vf / V = 0.82
That means 82% of the object's volume (and therefore, 82% of its mass, assuming uniform density) is submerged. Which means that 18% is above the water line.