user86894: I have 10s of private and public keys associated with 10s of different addresses. 
Now I have a test-net btc address "mfoxBS2TpoiUWrEV3sZopoEB6Pi2d7TE9N".
What operations can I perform to find the appropriate Public Key associated with given address?
UPDATE
I am not trying to find out reverse scenario of fetching a public key from address.
As I already have bunch of public keys. One of them have created the given address. And I just want to figure out which one is it from the whole bunch?

user76567: There is a step-by-step guide here and you can also test it on this site. 
You can also use this python library.
import os
os.environ['CRYPTOTOOLS_NETWORK'] = 'test'

from btctools import PublicKey

>>> pub = Publickey.from_hex('yourpubkeyhere')
>>> pub.to_address('P2PKH')
'mp9CpH3h25m7FZqsPBf2UfU9Gm4u41j9Eg'


86894: <p>I have 10s of private and public keys associated with 10s of different addresses. </p>

<p>Now I have a test-net btc address "<strong>mfoxBS2TpoiUWrEV3sZopoEB6Pi2d7TE9N</strong>".</p>

<p>What operations can I perform to find the appropriate <strong>Public Key</strong> associated with <strong>given address</strong>?</p>

<p><strong>UPDATE</strong>
I am not trying to find out reverse scenario of fetching a public key from address.</p>

<p>As I already have bunch of public keys. One of them have created the given address. And I just want to figure out which one is it from the whole bunch?</p>
 76567: <p>There is a step-by-step guide <a href="https://en.bitcoin.it/wiki/Technical_background_of_version_1_Bitcoin_addresses#How_to_create_Bitcoin_Address" rel="nofollow noreferrer">here</a> and you can also test it on <a href="https://gobittest.appspot.com/Address" rel="nofollow noreferrer">this</a> site. </p>

<p>You can also use <a href="https://github.com/mcdallas/cryptotools" rel="nofollow noreferrer">this</a> python library.</p>

<pre><code>import os
os.environ['CRYPTOTOOLS_NETWORK'] = 'test'

from btctools import PublicKey

&gt;&gt;&gt; pub = Publickey.from_hex('yourpubkeyhere')
&gt;&gt;&gt; pub.to_address('P2PKH')
'mp9CpH3h25m7FZqsPBf2UfU9Gm4u41j9Eg'
</code></pre>
