Answer:is this a question??? I’m so confused 
Explanation:
 
        
             
        
        
        
Alkali metals: left column of your periodic table (not hydrogen, but anything below it). They have one valence electron, which they are happy to share in a reaction. 
Halogens: second column from the right of your periodic table. They are one electron short of a full shell, so they are reactive in the opposite way that alkalis are--they want electrons. 
Atomic number (number of protons) is the big number on the periodic table square. Hydrogen's is 1. 
Atomic mass is a little number down below. For example, Hydrogen's is 1.008. 
Neutrons are a tricky subject, because different isotopes of the same element can have different numbers of neutrons. You can't generally get this from the atomic mass, because the atomic mass is a weighted average of naturally occurring isotopes. Hydrogen can have 0,1, or 2 neutrons. To answer this, you'd have to choose a particular isotope from the table of isotopes (a completely different chart from the periodic table) which has a certain number of neutrons: n = weight - Z. 
Valence electrons are the electrons in the outermost shell. (The column of the table). 
<span>
Number of principal shells is the row of the periodic table. </span>
        
             
        
        
        
The equation for electrical power is<span>P=VI</span>where V is the voltage and I is the current. This can be rearranged to solve for I in 6(a).
6(b) can be solved with Ohm's Law<span>V=IR</span>or if you'd like, from power, after substituting Ohm's law in for I<span>P=<span><span>V2</span>R</span></span>
For 7, realize that because they are in parallel, their voltages are the same.
We can find the resistance of each lamp from<span>P=<span><span>V2</span>R</span></span>Then the equivalent resistance as<span><span>1<span>R∗</span></span>=<span>1<span>R1</span></span>+<span>1<span>R2</span></span></span>Then the total power as<span><span>Pt</span>=<span><span>V2</span><span>R∗</span></span></span>However, this will reveal that (with a bit of algebra)<span><span>Pt</span>=<span>P1</span>+<span>P2</span></span>
For 8, again the resistance can be found as<span>P=<span><span>V2</span>R</span></span>The energy usage is simply<span><span>E=P⋅t</span></span>
        
             
        
        
        
Given: Velocity of light    c = 3.00 x 10⁸ m/s
Frequency f = 7.65 x 10⁷/s
Required: Wavelength λ = ?
Formula:  λ = c/f
λ = 3.00 x 10⁸ m/s/7.65 x 10⁷/s
λ = 3.92 m
        
             
        
        
        
Answer:
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Explanation:
Sound waves are caused by vibration ripples in water are caused by disturbance in the molecules