Bio expert
which of the following is an osmotic regulatory challenge that a fish living in salt water faces?
a. urea expulsion
b. salt expulsion
c. water expulsion
d. uric acid expulsion
is it a.?

climate change and pollution

is this a psat question, if so do not cheat try your best.

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

here's your answer.