For an off-axis orthotropic material in plane stress, find general an expression for the angle where the maximum/minimum values of material constants nxyx occurs. express your answer as a cubic equation for cos 20. for unidirectional b(4)/5505 boron-epoxy (e = 204.0 gpa, e, = 18.5 gpa, v12 = .23, g12 = 5.59 gpa), find the angles that solve the equation.

Ariver flows from north to south at 8 km/h. a boat is to cross this river from west to east at a speed of 20 km/h (speed of the boat with respect to the earth/ground). at what angle (in degrees) must the boat be pointed upstream such that it will proceed directly across the river (hint: find the speed of the boat with respect to water/river)? a 288 b. 21.8 c. 326 d. 30.2

The higher the astm grain-size number, the coarser the grain is. a)-true b)-false

Carbon dioxide gas expands isotherm a turbine from 1 mpa, 500 k at 200 kpa. assuming the ideal gas model and neglecting the kinetic and potential energies, determine the change in entropy, heat transfer and work for each kilogram of co2.