Which gas forms 21% of earth's atmosphere?
a.-argon
b.-carbon dioxide
c.-nitrogen
d.-oxygen

Number the steps from when a stimulus is received to when the body reacts

Iam stuck on this question! 45 points : ) how do increases in temperature affect the density of ocean water? answer choices: (a) density does not change (b) density increases (c) density becomes variable (d) density decreases

Soweto was the site of one of the that swept across south africa in the late 1970s. in his effort to end apartheid, desmond tutu turned to . the united states responded to south africa’s apartheid policy in the 1980s by .