The seasons we experience are caused by Earth's- tilted axis and the Sun

tilted axis and size

orbit and distance from the Sun

orbit and distance from the Moon

Models are non-visual ways of coummincating how someone thinks about something in the natural world

What must be true for natural selection to heppen

Dna and rna share a number of similarities,but they also differ in certain aspects of their structure. wich nitrogenous base is found in rna but is not found in dna