The unit expressed in 660 nm of light represents the wavelength of light. If you want to determine the frequency, you use the speed of light to relate the two. The formula is:
c = λν
where
λ is the wavelength
ν is the frequency
c is the speed of light = 3×10⁸ m
Apply SI units:
(3×10⁸ m) = (660×10⁻⁹ m)(ν)
Solving for ν,
<em>ν = 4.55×10¹⁴ s⁻¹</em>
        
             
        
        
        
Answer:
The answer to your question is
1.- Volume = 3.4 ml
2.- Volume = 0.61 ml
3.- Mass = 2872.8 pounds
Explanation:
Problem 1
Volume = 18 ml
mass = 35.6 g
density = 10.5 g/ml
Process
1.- Calculate the volume of silver
Formula

solve for volume 

Substitution

<u>volume = 3.4 ml</u>
2.- Problem 2
Total volume = ?
Volume = 18 + 3.4 
Volume = 21.4 ml
Data
mass = 8.3 g
density = 13.6 g(ml
volume = ?
Formula 

Solve for volume

Substitution

Result 
<u>volume = 0.61 ml</u>
3.- Problem 3
Data
volume = 345 gal
density = 1 g/ml
mass = ?
Formula

Solve for mass
mass = density x volume
Covert gal to ml
                             1 gal --------------- 3785 ml
                          345 gal -------------  x
                             x = (345 x 3785) / 1
                             x = 1305825 ml
Substitution
mass = 1 x 1305825
mass = 1305825 g
Convert g to pounds
                         1 g ------------------- 0.0022 pounds
               1305825 g ----------------   x
                         x = (1305825 x 0.0022)
                        <u> x = 2872.8 pounds</u>
 
        
             
        
        
        
Answer: 0.075 
Explanation:
(concentration in molarity)(volume in liter) = answer
0.15 mol/L *0.500L = 0.075 mol
 
        
             
        
        
        
Answer:
Hydrogen is usually classified as a group 1 element since it has one valence electron, just like group 1 metals.
Explanation:
 
        
             
        
        
        
Answer:
the moon but mass stays the same  
Explanation: