Which sums prove that the boards will create a triangular outline for the garden? Select all that apply.

For three lengths to form a triangle, the sum of any two sides must be greater than the third side. Here, 5 + 2.5 = 7.5 > 4, 4 + 2.5 = 6.5 > 5, and 4 + 5 = 9 > 2.5. So the sums in choices A, C, and E prove the boards can form a triangular outline.

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