Experimentally, it has been observed for single crystals of a number of metals that the critical resolved shear stress, τcrss, is a function of the dislocation density, rhoD, as where τ0 and A are constants. For some metal, the critical resolved shear stress is 3.14 MPa at a dislocation density of 1.60 × 104 mm-2. If it is known that the value of A for this metal is 1.52 × 10-3 MPa-mm, compute the τcrss (in MPa) at a dislocation density of 2.85 x 106 mm-2.