Saxophone A plays a 430 Hz tone, and at the same time saxophone B plays a tone of a different frequency. If a beat frequency of 5 beats/second can be heard, which of the
following could be the frequency played by saxophone B?
A. 425 Hz
B. 440 Hz
C. 430 Hz
D. 5 Hz

Identify the arrows that show the correct direction of heat transfer. 66°f 112°f 98°f

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.

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.