What are three human activities have transformed the biosphere?

Agriculture, Development, and Industrial growth.

yes its like the dead sea which is full of salt which makes you stay afloat

so yes an egg will float in salt

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)