If a bicyclist travels 30 kilometers in two hours, her average speed is… A - 30km/h
B - 60km/h
C - 15km/h
D - 2km/h

I will mark 5.0 star and heart if you explain it and answer correctly

The softest and hardest minerals are: softest hardest

If y gets smaller as x gets bigger and y have an relationship?

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.