Question 995528
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The length of the field is  {{{(280-2*60)/2}}} = {{{(280-120)/2}}} = {{{160/2}}} = 80 m.


Hence,  the diagonal of the field has the length  {{{sqrt(80^2 + 60^2)}}} = {{{sqrt(6400+3600)}}} = {{{sqrt(10000)}}} = 100 m.


<U>Answer</U>. &nbsp;100 m.