The main reason Earth have Seasons it's because of the Earth tilt. One side would be tilted to the sun which causes summer and the other side would be tilted away whitch causes Winter.
The S side of Earth for example is face to the sun which is summer
The N side of Earth of pointed away which is winter.
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Answer:
The reflection and rectilinear propagation of light helps in the formation of shadows and also tells light doesn't penetrate opaque materials.
The questions from this lot which could be tested in a scientific manner would be "what causes some people to be color-blind"
and
"what are the best shoes to wear when exercising"
Both of these questions can be tested in a scientific way through an experiment.
Answer:
I am not really sure, but it is probably Carbon Dioxide
Explanation: