An experiment is designed to see if the shells of sea snails are weakened by exposure to sea water which is more acidic than normal. Shells are placed in normal sea water, sea water that is more acidic than normal, and sea water that is more basic than normal.

The shells are checked every day at 8 AM. Which of the following is the dependent variable for this experiment?

exposure to sea water that is more acidic than normal
exposure to sea water that is more basic than normal
time
the strength of the shell

The answer is c hope this

Answer:   [a]:   "slate" .

Isso9

Stars are born within the clouds of dust and scattered throughout most galaxies. a familiar example of such as a dust cloud is the orion nebula. turbulence deep within these clouds gives rise to knots with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction. as the cloud collapses, the material at the center begins to heat up. known as a protostar, it is this hot core at the heart of the collapsing cloud that will one day become a star. three-dimensional computer models of star formation predict that the spinning clouds of collapsing gas and dust may break up into two or three blobs; this would explain why the majority the stars in the milky way are paired or in groups of multiple stars.therefor, i would say the answer is: dust and gases contract.i hope this ! < 3