Question

Which layers are impermeable ?

layer of loose soil

layer of sand

layer of gravel

layer of hard clay

solid rock
HELP ASAP!

Answer 1

Layer of sand, layer of hard clay and layers of loose soil

Answer 2

Impermeable and/or non-porous materials include clay, non-fractured igneous and metamorphic rocks. Porous/permeable layers are called aquifers; impermeable layers called aquiludes.