What is the expected range of LBC of a 2.5 m long, 15 cm diameter timber prop?

The load-bearing capacity (LBC) of a timber prop depends on its dimensions and the type of wood used. For a 2.5 m long timber prop with a diameter of 15 cm (which is approximately 0.15 m), the expected range of LBC typically falls within 50 to 60 kN (kiloNewtons). This assumes a standard load capacity for timber props used in mining and construction to support roofs or walls.

Let's analyze each option:

Option A: "5 - 10 kN" - This range is too low for a timber prop of this size and diameter.

Option B: "15 - 20 kN" - This range is still too low for a timber prop of this size and diameter.

Option C: "50 - 60 kN" - This range is within the expected load-bearing capacity for a timber prop of this size and diameter.

Option D: "120 - 130 kN" - This range is too high for a timber prop of this size and diameter.

Therefore, the correct answer is Option C: 50 - 60 kN.