Update Password_Storage_Cheat_Sheet.md

Fix a sentece.

cheatsheets/Password_Storage_Cheat_Sheet.md

@@ -71,7 +71,7 @@ For example, one peppering strategy is hashing the passwords as usual (using a p
 
  The work factor is the number of iterations of the hashing algorithm that are performed for each password (usually, it's actually `2^work` iterations). The work factor is typically stored in the hash output. It makes calculating the hash more computationally expensive, which in turn reduces the speed and/or increases the cost for which an attacker can attempt to crack the password hash.
 
-When you choose a work factor, strike a balance between security and performance. Though higher work factors make hashes more difficult for an attacker to crack, they will slow down the process of verifying a login attempt. If the work factor is too high, the performance of the application may be degraded, which could used by an attacker to carry out a denial of service attack by exhausting the server's CPU with a large number of login attempts.
+When you choose a work factor, strike a balance between security and performance. Though higher work factors make hashes more difficult for an attacker to crack, they will slow down the process of verifying a login attempt. If the work factor is too high, the performance of the application may be degraded, which could be used by an attacker to carry out a denial of service attack by exhausting the server's CPU with a large number of login attempts.
 
 There is no golden rule for the ideal work factor - it will depend on the performance of the server and the number of users on the application. Determining the optimal work factor will require experimentation on the specific server(s) used by the application. As a general rule, calculating a hash should take less than one second.