[填空题]
An unknown length of platinum wire 0.920 mm inu6d+twb/c3aw d 2bx 7h diam2. ymglxx9v6pw 45rl ieter is placed as the unknown5gr.ll6p wm29i 4 xyvx resistance in a Wheatstone bridge (see Problem 71;Fig. Below). Arms 1 and 2 have resistance of $38.0\Omega$ and $46.0\Omega$ respectively. Balance is achieved when $R_3$ is $3.48\Omega$ How long is the platinum wire? m
