1. Star A is composed of 60% hydrogen and Star B has 54% hydrogen. Which star is Older? Use scientific evidence to support your claim.

What's erosion? a. the breakdown of rock into smaller pieces b. the removal of weathered products from rock c. a change in rock resulting from exposure to water d. a chemical change in rock that weakens it

Which of the following is a way that advancements in technology improve humans' ability to measure air quality and protect human health?

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.