Which materials undergo radioactive decay? Check all that apply.

atoms that are unstable
elements that have a half-life
atoms that release energy and particles
elements that have turned into a new element
elements that have a consistent number of particles

Click the item in the left column. use the plus sign to move it up or the minus sign to move it down until it matches the correct entry in the right column. lock your answer in place by clicking the square beside the item. (a checkmark means it is locked.) amazon basin a atacama desert b andes mountains c lake titicaca d peru e patagonia f brazil g chile h suriname

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

What is unusual about the iraq mountains ,in spite of their old age?