Answer:
It would be A.
Explanation:
The scale goes from 0 to 14, With 0 being acidic and 14 being basic.
So if 7 is neutral, then anything less than 7 is moving more towards being more acidic. Anything higher than 7 is moving towards being more basic.
Density = (mass) divided by (volume)
We know the mass (2.5 g). We need to find the volume.
The penny is a very short cylinder.
The volume of a cylinder is (π · radius² · height).
The penny's radius is 1/2 of its diameter = 9.775 mm.
The 'height' of the cylinder is the penny's thickness = 1.55 mm.
Volume = (π) (9.775 mm)² (1.55 mm)
= (π) (95.55 mm²) (1.55 mm)
= (π) (148.1 mm³)
= 465.3 mm³
We know the volume now. So we could state the density of the penny,
but nobody will understand what we have. Here it is:
mass/volume = 2.5 g / 465.3 mm³ = 0.0054 g/mm³ .
Nobody every talks about density in units of ' gram/(millimeter)³ ' .
It's always ' gram / (centimeter)³ '.
So we have to convert our number for the volume.
(0.0054 g/mm³) x (10 mm / cm)³
= (0.0054 x 1,000) g/cm³
= 5.37 g/cm³ .
This isn't actually very close to what the US mint says for the density
of a penny, but it's in a much better ball park than 0.0054 was.
If you search that click the first link ;)
<span>C is the correct answer. Electron microscopes require a vacuum to work, so living cells cannot be seen because they cannot respire. Light microscopes use a ray of visible light instead of a beam of electrons to magnify something so it can be seen by the naked eye. There are two different types of electron microscope: transmission (TEM) and scanning (SEM).</span>
Answer:
1.33
Explanation:
speed of light in vacuum, c = 3 x 10^8 m/s
speed of light in medium, v = 2.26 x 10^8 m/s
The refractive index of the medium is given by
μ = speed of light in vacuum / speed of light in medium
μ = (3 x 10^8) / (2.26 x 10^8)
μ = 1.33