Consider the following general scheme:

How does benzyl ether protect the 1° alcohol? What are the reagents used in the first step? 

It protects the alcohol from reacting with the reagents used in the next steps. The reagents used in the first step are as follows:

It protects the alcohol from activating the reagents used in the next steps. The reagents used in the first step are as follows:

It protects the alcohol from activating the reagents used in the next steps. The reagents used in the first step are as follows:

It protects the alcohol from reacting with the reagents used in the next steps. The reagents used in the first step are as follows: