Is Petra man made or natural?

What is the best indicator in geography? What are the characteristic activities of interphase? What age takes place in 1550? Would you say that systems that have higher efficiency ratios than other systems will always have higher utilization ratios than those other systems? How toxic is the trumpet vine flower? What affects color of minerals? What refers to a small piece of celestial debris that has struck the surface of a planet? How do you work out density of an alloy given its make up? Where is Edwin Hubble's grave? Can lava melt a person standing in it? What is the geographic significance of the two tropic lines? What is the relationship between the light dependent reaction and Calvin cycle? How are viruses different from bacteria Apex? When you access a port catheter do you use is sterile technique or aseptic? How much ginkgo to take daily? Will the molar concentration of the NaOH be reported as too high or too low? How much does a supernova weigh? What do non coding DNA do? Should microwave outlet cover be removed? How do people pay taxes in Kenya?

Is Petra man made or natural?