your employer has the ability to protect you from cave-ins and other hazards by using adequately-designed protection systems in excavations, but these are not required when an excavation is made entirely in stable rock or is less than how deep?

What does a triple-beam balance require the user to do? add the numbers from the three sliders to determine the mass of an object multiply the numbers from the three sliders to determine the mass of an object add the numbers from the three sliders to determine the volume of an object multiply the numbers from the three sliders to determine the volume of an object