[mod3-04] fix some more typos

mod3-04.html

@@ -494,7 +494,7 @@ <h2>WLAN Discovery</h2>
 							<li>In <strong>passive</strong> mode, <u>the AP signal its presence by the periodic transmission of a Beacon management frame</u>, which advertise the SSID and the association parameters.</li>
 							<li>In <strong>active</strong> mode, <u>the STAs send, on every channel iteratively, a Probe Request management frame</u> (as unicast if the SSID is known, broadcast otherwise) containing supported network modes and data rates.</li>
 						</ul>
-						<p>The <strong>AP can be configured to hide its SSID</strong> as a form of additional security. by disabling Beacon frames tranmission.</p>
+						<p>The <strong>AP can be configured to hide its SSID</strong> as a form of additional security, by disabling Beacon frames transmission.</p>
 						<p><u>A STA can connect to an hidden SSID only if it knows the SSID in advance</u> in order to send a directed probe request. The hidden AP will "reveal" itself through a probe response.</p>
 					</section>
 					<section>