About 3% of the water on earth is freshwater. only about 40% of that freshwater is available for human use. why is so much freshwater unavailable for human use? a) it is frozen. b) it is polluted. c) it is salt water. d) it is in aquifers. 2) the deepest place in the seafloor is called the a) abyssal plain. b) marianas trench. c) aleutian trench. d) hydrothermal vent. 3) tides are caused by a) gravity. b) heat. c) waves. d) winds.

These are the correct answers you guys can definitely trust me on:

#1. It is frozen, when we need it, people with cut it out

#2. The deepest part of the ocean in the Mariana's Trench

#3. Gravity: Tides are caused by the gravitational interaction between the Earth and the Moon. The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.