<u><em>Answer:</em></u>
<u><em>The speed is  </em></u>
<u><em>=
</em></u>
<u><em>30
</em></u>
<u><em>m
</em></u>
<u><em>s
</em></u>
<u><em>−
</em></u>
<u><em>1
</em></u>
<u><em>
</em></u>
<u><em>Explanation:
</em></u>
<u><em>The speed of a wave is given by
</em></u>
<u><em>
</em></u>
<u><em>speed
</em></u>
<u><em>(
</em></u>
<u><em>m
</em></u>
<u><em>s
</em></u>
<u><em>−
</em></u>
<u><em>1
</em></u>
<u><em>)
</em></u>
<u><em>=
</em></u>
<u><em>frequency(Hz)
</em></u>
<u><em>×
</em></u>
<u><em>wavelength (m)
</em></u>
<u><em>
</em></u>
<u><em>The frequency is  </em></u>
<u><em>f
</em></u>
<u><em>=
</em></u>
<u><em>100
</em></u>
<u><em>H
</em></u>
<u><em>z
</em></u>
<u><em>
</em></u>
<u><em>The wavelength is  </em></u>
<u><em>λ
</em></u>
<u><em>=
</em></u>
<u><em>0.3
</em></u>
<u><em>m
</em></u>
<u><em>
</em></u>
<u><em>The speed is
</em></u>
<u><em>
</em></u>
<u><em>v
</em></u>
<u><em>=
</em></u>
<u><em>λ
</em></u>
<u><em>f
</em></u>
<u><em>=
</em></u>
<u><em>0.3
</em></u>
<u><em>⋅
</em></u>
<u><em>100
</em></u>
<u><em>=
</em></u>
<u><em>30
</em></u>
<u><em>m
</em></u>
<u><em>s
</em></u>
<u><em>−
</em></u>
<u><em>1
</em></u>
<u><em>
</em></u>
<u><em></em></u>
<u><em></em></u>
<u><em></em></u>
 
        
             
        
        
        
The threats as well as the risk and vulnerabilities are present with the WLAN. The WLAN would encounter security issues with the range of the signal which is wireless, SSID broadcasting, password security and the packet sniffing or the capturing of signal.
        
             
        
        
        
Answer:
To solve the problem, first, 
a) The computer account should be reset.
b) Deactivate the computer from the domain.
c) Then, rejoin it to the domain.
Explanation:
A domain is a network that  allows different computers to function and operate from a common server. A domain may or may not be protected by a password. Setting up a domain provides additional security thereby blocking other computer networks from having access to it. When a person is experiencing difficulties in logging into a domain, there are certain things to be done to resolve the issue.
First, reset the computer account.
Secondly, deactivate the computer from the domain.
Third, Rejoin it back to the domain.