What does it mean when a compound’s chemical formula does not include any numbers?

Explanation:An example of such a substance is table salt. The chemical formula for table salt is NaCl. ... That there are no numbers present in the chemical formula means that there is one atom of each element present in the molecule. The Periodic Table reveals that Na is the symbol for sodium, and Cl is the symbol for chlorine.

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

here's your answer.

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.