Answer:
The accuracy can be improved by making sure no external force is applied, i.e the marbles should accelerate under gravity only during each trial.
Explanation:
Accuracy is a term used to describe the relationship between a measured value to the real value. When a measured value is accurate, it implies that there is little or no error in the value; thus it is equal to the real value or very close to it.
Since this experiment is to determine the speed with which the marble roll down the plane, they should ensure uniform acceleration through out the trials. The marbles should be allowed to move under the influence of gravity only without applying any external force.
It is a single replacement reaction. Li and Mg switch places.
The density of metal = 4.5 g/ml, and the metal = Titanium
<h3>Further explanation </h3>
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:

ρ = density
m = mass
v = volume
mass of metal=27 g
volume = 6 ml
The density :

The metal with a density of 4.5 g/ml is Titanium
The location of the negative charges is evenly distributed throughout the entire atom.
J. J. Tomson concluded that atoms are divisible and that the corpuscles are their building blocks.
Atoms are made up of smaller particles.
J. J. Thomson discovered the electron ( the negative charges of the atom) in 1897.
His "plum pudding" model (1904) suggested: the electrons are embedded in the positive charge and evenly distributed throughout the entire atom.
With this model, he abandoned his earlier hypothesis that the atom was composed of immaterial vortices.
Later, Rutherford demonstrate that J.J Thompson's Plum Pudding model was not accurate.
More info about Thomson’s plum pudding model: brainly.com/question/6319700
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