Explanation:
Percentage ethylene by weight = 57%
Percentage propylene by weight = 43%
Suppose in 100 grams of polymer:
Mass of ethylene = 57 g
Mass of propylene = 43 g
Moles of ethylene = 
Moles of propylene = 
1 mole =
molecules/ atoms
Units of ethylene = 
Units of propylene = 
a) Fraction of ethylene units:

b ) Fraction of propylene units:

Answer: The frequency of the wave is 0.5 hertz.
Explanation:

= Frequency of the wave
= speed of the light in m/s
= Wavelength of the wave.
Here in question we are given with speed of the infrared light. So, we will replace the value of speed of light(c) from the given value of the speed of the infrared light.
Speed of infrared light = 6 m/s

The frequency of the wave is 0.5 hertz.
the law of thermodyanamic is the restatement of the law of conservation of energy
Magnesium oxide is an ionic compound with a very high melting point and which requires a large amount of energy for melting.
<h3>What are ionic compounds?</h3>
Ionic compounds are compounds which are formed between oppositely charged ions which are held together by electrostatic forces of attraction between the oppositely charged ions.
Ionic compounds are formed when metal atoms donate electrons to non-metals atoms to form ions.
Magnesium oxide is an ionic compound.
The nature of bonding is ionic bonding.
It has a crystalline lattice structure.
The forces of attraction is electrostatic forces of attraction.
It has a high melting point of 2,852 °C, and thus requires a large amount of energy go melting to occur.
Therefore, magnesium oxide is an ionic compound which requires a large amount of energy for melting.
Learn more about ionic compounds at: brainly.com/question/11638999