�?�?t ε l ρ l v l + �?�?ε l ρ l v l v l = ε l �?�?τ l + ε l ρ l g �?ε l �?p �?β v l �?v s Notice: Drillopedia.com can be a submission-dependent information-sharing web page. Contributors submit info based on Successfully Submitted (Awaiting Approval)