Determine the critical height h of the water level that causes the concrete gravity dam to be on the verge of tipping over due to water pressure. the density of concrete is ρc = 2.40 mg/m3. suppose that hd = 38 m. hint: work the problem using a 1-m width of the dam.

Scientists follow specific processes in order to determine valid explanations and conclusions from observations. david observed strange lights in the sky above his home outside of roswell, new mexico. the only explanation that makes sense to him is that there are ufos in the area. what should david do next to verify his explanation?