Water at 100 degree Centigrade. a.
boil

b.
boiled

c.
boils

d.
boiling

Based on the information in the passage, what conclusion can the reader make?

The greatest gift the sumerians gave the world was the invention of writing. the sumerians were wealthy people. they needed some way to keep track of what they owned. they began drawing pictures. they used a reed as a pen. they drew on soft pieces of clay. the soft clay was then dried in the sun. the tablet became a permanent record. later, the sumerian drawings changed into wedge-shaped symbols. this kind of writing is called cuneiform. by putting symbols together, the sumerians could write entire sentences.

What is the main idea of this paragraph from the volcanoes section of the ready. gov website