C# send image over HTTP

I have a small HTTP-Server here written in C# and until now I only needed to send raw text back to the sender. But now I have to send a JPG-Image and I dont unterstand how.

this is what I have now:

// Read the HTTP Request
Byte[] bReceive = new Byte[MAXBUFFERSIZE];
int i = socket.Receive(bReceive, bReceive.Length, 0);

//Convert Byte to String
string sBuffer = Encoding.ASCII.GetString(bReceive);

// Look for HTTP request
iStartPos = sBuffer.IndexOf("HTTP", 1);

// Extract the Command without GET_/ at the beginning and _HTTP at the end
sRequest = sBuffer.Substring(5, iStartPos - 1 - 5);
String answer = handleRequest(sRequest);


// Send the response
socket.Send(Encoding.UTF8.GetBytes(answer));

I think I have to do some kind of filestream instead of a string but I really have no glue..