What texture of rock will develop when lava cools so quickly that crystals do not form? a. glassy b. aphanitic c. phaneritic d. porphyritic

What structure on the south african coast has a range of 63 km and releases flashes every 30 seconds?

What evidence does the writer give to support his argument about coral reefs? a) he speaks of the activities of coral polyps. b) he describes the composition of the great barrier reef. c) he emphasizes the ways in which coral reefs are fragile. d) he points out the ways that scientists do research on the reefs.

Data courtesy of the un development programme 2006-2008 and world bank 2009 the chart above compares measures of development using the hdi and gdp. why might turkey rank lower in the hdi indicator even though it has a high gdp? a. turkey has a lower gdp than comparable countries in the hdi ranking. b. turkey must increase its hdi to have a higher gdp ranking. c. turkey is only compared to other european countries in gdp, not to the world, as it is in the hdi. d. turkey may struggle to provide adequate education or health care, or it may have a lower life expectancy.