As you watch a surfer ride a wave toward the shoreline what is the shoreline a cartesian b reference point c coordinate plane d displacement reference

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Organelles are 1. responsible for producing power for the cell 2. tiny structures in the cell that carry out the cell's activities 3. responsible for digestion in the cell 4. found outside of the membrane

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.