Answer to Question 1
Section 2703 of ECPA provides investigators with five mechanisms for compelling an Internet Service Provider to disclose information that might be useful in an investigation of a hacker. A search warrant is preferable to a simple subpoena. Subpoenas aren't good enough for obtaining unopened emails as listed in paragraph number two. Further, under paragraph five, the ECPA does not require notification to the subscriber when using a search warrant. While both procedures can request non disclosure, or at least a delay of disclosure to the defendant, a search warrant has more power.
Answer to Question 2
There are websites that can be used to send traceable emails. This works kind of like sending a registered letter via the postal service in that the sender will receive confirmation that the message was received. One example of such a service is confirm.to. For a modest fee, this website attaches a line of code to your email and then sends it on to the intended recipient. As soon as that person clicks on your email message, a message is automatically sent by confirm.to telling you the IP address, date, and time the email was opened.
Molecular mechanisms that convey positional information.
Scientific Method
Alternative method of testing cardinal field of gaze
Balance the given redox reduction equation in basic solution using the half reaction method
Linear programming problems using the simplex method.