�?�?t ρ l k + �?�?x i ρ l k v l = �?�?x j μ + μ t σ k �?k �?x j + G k �?ρ l ε �?Y M Note: Drillopedia.com can be a submission-based mostly understanding-sharing web page. Contributors submit info primarily based on their own know-how and encounter. End users ought to use their discretion when using the knowledge