The electric charge that eventually forms lightning is built up due to
a. static electricity in the air
b. sudden heating of the air
c. the movement of raindrops and hail within the cloud
d. the formation of raindrops out of rapidly condensing water vapor

Describe the change in phase and temperature as water moves from the oceans to the atmosphere and then returns to earth again as rain. a) evaporation : temperature increases; condensation : temperature decreases; precipitation (rain) : temperature decreases b) evaporation : temperature increases; condensation : temperature decreases; precipitation (rain) : temperature increases c) evaporation : temperature decreases; condensation : temperature decreases; precipitation (rain) : temperature decreases d) evaporation : temperature increases; condensation : temperature increases; precipitation (rain) : temperature decreases

Which part of the spine is likely to cause a nerve signal to travel faster? a. backbones b. white matter c. nuclei d. gray matter

Describe surface tension in a group of bonded water molecules