Using only the human eye how do objects in the sky appear to differ one another

Which of the following is not a symptom of desertification? a) decrease in salt content of the soil b) lowering of the water table c) reduced surface water d) increased soil erosion e) loss of native vegetation

_is a product of the first stage of photosynthesis. atpglucosecarbon dioxidewater

Why does the earth spin slowly, not faster? is it possible to prove it scientifically? can you prove it with math?