1. The problem statement, all variables and given/known data Below are six crates at rest on level surfaces. The crates have different masses and the frictional coefficients [given as (μs, μk) ] between the crates and the surfaces differ. The same external force is applied to each crate, but none of the crates move. Rank the crates on the basis of the frictional force acting on them. Rank from largest to smallest. To rank items as equivalent, overlap them. Items: (mass in kg, μs, μk) A. 250, 0.2, 0.1 B. 1500, 0.3, 0.1 C. 500, 0.6, 0.3 D. 750, 0.6, 0.5 E. 600, 0.8, 0.5 F. 750, 0.4, 0.3 2. Relevant equations fs ≤ μs * m * g 3. The attempt at a solution I used the equation fs = μs * m* g and got the answer wrong. Now I am just completely confused. Any help will be appreciated, thanks.