Fig. 19-4 shows two wires, in cross section, carrying 7.0 amperes out of the page. determine the total magnetic field, due to both wires, at point x midway between the wires.

Distance covered = speed x timethe distance traveled going against the stream = distance traveled with the stream.therefore it is the speed and the time that are the variables.as he travels the same distance both ways, speed x time is the same for each way.going upstream his speed is 4 kph; going downstream his speed is 6 kph.therefore we have two simultaneous equations: time upstream x 4 = time downstream x 6time upstream + time downstream = 60 minutestherefore we have the equation: time upstream = 6/10 hour, time downstream therefore = 4/10 hour.distance traveled at 4km/hr in 6/10 hour = 24/10 = 2.4km.check: distance traveled at 6km/hr in 4/10 hour = 24/10 = 2.4km.

This  kingdom  is  made  up of species that  do  not really easily fit into other kingdoms such as the plant, animal,and  fungi  kingdom. some protists, such as the paramecium  and  amoeba, feed  on  other  organisms  while others such as algae are able to  make their own food  through the process of photosynthesis.

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