Question 673371
{{{B = (r^2)/30F}}}
{{{r^2 = 30F(B)}}}
...
r^2 = 30(.65)(185)
r^2 = 3607.5
...
{{{sqrt(r^2)}}} = +/- {{{sqrt(3607.5)}}}
r = +/- {{{sqrt(3607.5)}}}
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