A short paragraph comparing the effectivemess of simple and complex machines​

Which types of seismic waves travel through earths interior? select all that apply. a) l waves b) p waves c) s waves

What tests were able to determine when continental crust was formed?

Why do so many children develop illnesses in southern africa? a. poor nutrition due to poverty c. very bad air pollution b. climate many diseases thrive d. declining life expectancy