What are two reasons why the height of clouds vary from day to day?

Some clouds form as air warms up near the Earth's surface and rises. ... That warmed air starts to rise because, when warm, it is lighter and less dense than the air around it. As it rises, its pressure and temperature drop causing water vapor to condense.

https://scied.ucar.edu/learning-zone/clouds/how-clouds-form

I hope this helped :)

a time line cause it goes from 685 to 978

i'm guessing this is from edg enuity so the answers would be, from top to bottom,

theodor schwann

matthias schleiden

robert hooke

rudolph virchow

anton van leeuwenhoek