What are stromatolites?

eukaryotes with nuclei that were formed by a single cell or many cells during the precambrian time

soft-bodied organisms resembling the types of jellyfish, worms, and coral that live in the oceans today

layered mounds of calcium carbonate that were deposited by algae during the precambrian time

Which statements about wells are true? check all that apply. a) wells bring groundwater from the unsaturated zone to the surface of the water. b) wells need to be drilled below the water table. c) if water is pumped from a well too quicky, the well may run dry. d) water from wells is generally not safe to drink. e) water gushes from artesian wells due to pressure.

Sam hated the long nights of winter! his mother called him in from playing so early: around 4: 30 pm! it is usually dark out when sam is eating supper. what letter represents the long nights where sam lives? a) a. b) b. c) c. d) d.

The separation of northern ireland from the republic of ireland is an example of