Alina is able to swim at a rate of about 2.5 miles per hour. talia is able to swim at a rate of 1.8 meters per second. which statement comparing the two swimmers is accurate?
1 mile=1,609 meters

alina swims about 0.7 miles per hour faster than talia.
talia swims about 0.7 miles per hour faster than alina.
alina swims about 1.5 miles per hour faster than talia.
talia swims about 1.5 miles per hour faster than alina.

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.