Answer:
it is chemical reactivity (D)
Explanation:
it is because chemical properties are properties that can be measured and observed only when matter undergoes a change to become an entirely different kind of matter.Which they include Chemical reactivity,flammable,and the ability to rust.And Chemical reactivity is the ability of matter to react chemically with other substances.
A) red light
red lights are an example of an electromagnetic wave. visible lights are the only electromagnetic waves we can actually see on the spectrum. red, in particular has the biggest wavelength.
b) ocean waves
ocean waves are not an electromagnetic wave. in fact, it’s a mechanical wave. electromagnetic waves can travel through a vacuum, that is empty space, but mechanical waves cannot.
c) sound waves
sound waves are also not an electromagnetic wave. it’s a mechanical wave. you cannot hear electromagnetic waves.
d) earthquakes
an earthquake is also not an example of electromagnetic waves. it’s a mechanical wave.
hope this helps!
El cerebro, la medula espinal, y los nervios.
Answer:
62.5 %
Explanation:
Let the initial intensity of unpolarized light is Io.
After first polariser the intensity of light becomes I'.
So, 
Now it passes through another polariser. The angle between the first polariser and the second polariser is given by Ф. The intensity is I''.
According to the law of Malus

Here, Ф = 30 degree

The percentage change in the intensity is given by

= 62.5 %
Answer:
a)F=3 x 10⁻⁷ N
b)x=2.405 m
Explanation:
Given that
m₁=295 kg
m₂=595 kg
d= 4.1 m
a)
m₃=63 kg
r=d/2 = 2.05 m
The force between the mass m₁ and m₃

by putting the values


F₁₃=2.94 x 10⁻⁷ N
The force between the mass m₂ and m₃
by putting the values


F₂₃=5.94 x 10⁻⁷ N
The net force F
F= F₂₃- F₁₃
F=5.94 x 10⁻⁷ N-2.94 x 10⁻⁷ N
F=3 x 10⁻⁷ N
b)
Lest take at distance x from mass m₂ net force is zero.


Form above two equation



x²=2.01(4.1-x)²
x=1.42 (4.1-x)
x=5.82 - 1.42x
x=2.405 m