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Answer:
length of diagonal d is 50 m. (first option is correct)
Step-by-step explanation:
using pythagoras theorem
here 40 and 30 are the legs of the triangle so let them be a and b respctively.
And d is the hypotenuse so let it be c
a^2 + b^2 = c^2
40^2 + 30 ^2 = d^2
1600 + 900 = d^2
2500 = d^2
[tex]\sqrt{2500} = d[/tex]
50 = d