If a heavy commercial truck carries a 10,000 kg (10-tonne) industrial machine on a steel trailer bed with a friction coefficient (koeficijent trenja) of μ = 0.2, what forward securing force is required to achieve 0.8g forward restraint?

1. 6,000 daN (or equivalent securing force for 6 tonnes, since friction holds 2 tonnes and lashings/blocking must hold the remaining 6 tonnes)
2. 8,000 daN entirely from lashings with zero contribution from friction
3. 2,000 daN only
4. Zero securing force if the machine has rubber feet