Because p and s waves travel faster through the earths mantle than through earths crust, scientists know that the mantle is and than the crust.
a: liquid; denser
b: solid; less dense
c: liquid; less dense
d: solid; denser

The declining axolotl population in mexico city is an example of in overcrowded cities. a. the surpassing of support capacity b. changes to natural environments and native species c. the lack of safe homes and tenured spaces d. the effects of a growing urban heat island