a compound strip of brass and iron 10cm long at 20c is held horizontally with the iron uppermost. when heated from below with a bunsen burner. the temperature of the brass is 820c and that of the iron is 770c. calculate the difference in length of the iron and the brass( coefficient of linear expansion of brass and iron are 0.000019c and 0.000012c respectively ​

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s.part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.