Answer:True
Explanation:
Water is said to be hard when it contains calcium ions or magnesium ions dissolved in it. These ions are able to react with soap in such a way that the soap is prevented from forming lather with the water. Hard water occurs when water passes over calcium or magnesium bearing minerals and dissolves some of it. Hardness due to the presence of calcium ions can easily be removed by boiling the water.
 
        
             
        
        
        
Answer:
The answer is D) White Light!
 
        
             
        
        
        
Answer: 
Explanation: 
Engineering notation : It is the representation of expressing the numbers that are too big or too small and are represented in the decimal form times 10 raise to the power.  It is similar to the scientific notation but in engineering notation, the powers of ten are always multiples of 3.
The engineering notation written in the form:
 
where,
a = the number which is greater than 0 and less than 999
b = an integer multiple of 3
Now converting the given value of 2,469,100 into engineering notation, we get  
Hence, the correct answer is, 
 
        
             
        
        
        
Answer:
By bonding due to the attractive forces
 
        
             
        
        
        
Answer:
Another name for light is ¨Electromagnetic Radiation, luminous energy, and/or radiant energy.¨
Explanation:
Light is the electromagnetic radiation that´s capable of causing a visual sensation and has wavelengths from about 380 to about 780 nanometres. Electromagnetic radiation includes Radio Waves, Microwaves <u>(used in microwaves)</u>, Infrared Radiation <u>(heat)</u>, Visible Light <u>(the colors we see)</u>, Ultraviolet <u>(the UV radiation that causes sunburns)</u>, X-Rays <u>(used in medical X-Rays)</u>, and Gamma Rays <u>(which can be used to treat cancer)</u>. Light waves are transverse waves because they only travel east or west, but their crests and troughs face north and south (if desplayed on a coordinate grid). They wouldn´t be longitudinal waves because these waves don´t have vertical crests and troughs.
I hope this helps!