C rock layers... hope this helped
Its a bad idea, because you are taking the saltwater marsh away from the ecosystem... And turning it into a cement covered ground, for more houses... Then the animals (or other things) that live there, will die... and have to find another place to live...
~therefore... The bad thing is, that they shouldnt fill the marsh with dirt, and cement... Because bad things could happen to the creatures that already live there.
U_____________W________________V
UV=13
UW=2y-9
WV=y-5
UV=UW+WV
UV=(2y-9)+(y-5)=2y-9+y-5=3y-14
13=3y-14
27=3y
y=27/3=9
Solution is A, y=9
The lower levels of the pyramid must also grow-for more people to consumer higher-end items, there must be more people to make those items.