The water cycle describes how water moves through the earth's crust atmosphere and oceans. Heat from the Sun causes liquid water to evaporate from rivers, lakes and oceans
and it becomes a gas called water vapour.. As the gas rises, it condenses and
to create droplets.
Water returns to the ground as solid hail and snow or liquid rain and sinks into the earth.
Below the ground it forms
where water is held between grains in rock
layers, and
Where aquifers intersect or cut the surface of the ground
the liquid water flows out to form
and
Differences in
elements, such as oxygen, can be used to estimate the and
of
water. A process is an event or series of events that cause a change to occur.

Suggest why placing wheels under a heavy box reduces the neccessary force required to push it along at a constant speed.

Speed is the ratio of the distance of an object moves to

Mr. j, age 42, is a construction worker in las vegas. he recently noticed that a mole on his face seemed to be getting larger and darker. at first he did not worry because he was in the sun a lot and assumed the change may have been caused by sunburn. after a month, not only was the mole larger and darker, but it appeared to be “bumpy.” his doctor diagnosed a malignant melanoma skin cancer following biopsy of the nevus. mr. j reports pain in his right shin that does not go away when he puts his feet up or sleeps. discussion questions 1. relate mr. j’s skin changes to the warning signs for malignant melanoma. (see malignant melanoma.) 2. discuss the normal progression of this malignancy. what is the significance of the bone pain that mr. j is experiencing? (see malignant melanoma.) 3. discuss the treatment available for this patient and the prognosis for recovery. (see malignant melanoma.)