23) Which of the following best describes how geysers erupt? Water suddenly boils in disconnected voids and cracks above the water table, causing the aquifer to explosively fragment. B) Water slowly boils in a network of vertical cracks above the water table, sending up a plume of steam and hot water. C) Water below the water table slowly boils in a vertical crack or natural conduit, causing a plume of condensed water vapor to rise above the vent. D) Water in a saturated, natural conduit suddenly boils, sending a plume of steam and hot water into the air above the vent. 24) Which one of the following is the one best measure of the wetness or dryness of a region? A) total annual precipitation B) mean annual temperature C) difference between annual precipitation and evaporation potential is a semiarid region. 25) A A) desert B) steppe C) subtropical high D) rainshadow desert 26) All of the following statements concerning dry lands are true EXCEPT A) precipitation totals are low; dew points are lower in the summer than winter B) evaporation potential exceeds actual precipitation C) storms are infrequent D) Lots of running water is present in these areas 27) When a permanent stream enters a desert area, what happens to the water in it? A) It increases. B) It decreases. C) It is unchanged, because it is a permanent stream. 28) Inselbergs are iecbergs floating in a hot spring at B) blowouts cut from bedrock in mountainous areas C) lithified rock formed by cementation of wind-deposited, dune sands D) bedrock hills in a highly eroded desert landscape 29) How are sand grains transported by the wind? A) high in the moving air column as suspended load B) by saltation in the first few meters above the land surface C) by deflation of abraded desert pavement D) by being picked up in swirling dust clouds and carried to distant blowouts 30) Broad, shallow depressions excavated by sediment removal in deserts are called A) yardangs B) ventifacts C) blowouts D) flats