Response.Output.Write() allows you to write formatted output. 

Add an OnMouseOver attribute to the button. Example:
btnSubmit.Attributes.Add("onmouseover","someClientCodeHere();"); 

Integer, String, and Date. 

Server-side code executes on the server.
Client-side code executes in the client's browser.

The answer is server-side code since code-behind is executed on the server.  However, during the code-behind's execution on the server, it can render client-side code such as JavaScript to be processed in the clients browser.  But just to be clear, code-behind executes on the server, thus making it server-side code. 

All user input data validation should occur on the server at a minimum.  Additionally, client-side validation can be performed where deemed appropriate and feasable to provide a richer, more responsive experience for the user.

Valid answers are:
·  A DataSet can represent an entire relational database in memory, complete with tables, relations, and views.
·  A DataSet is designed to work without any continuing connection to the original data source.
·  Data in a DataSet is bulk-loaded, rather than being loaded on demand.
·  There's no concept of cursor types in a DataSet.
·  DataSets have no current record pointer You can use For Each loops to move through the data.
·  You can store many edits in a DataSet, and write them to the original data source in a single operation.
·  Though the DataSet is universal, other objects in ADO.NET come in different versions for different data sources. 

The Global.asax (including the Global.asax.cs file) is used to implement application and session level events.

This is where you can set the specific variables for the Application and Session objects.