During which geologic epoch do scientists infer that the earliest grasses first appeared on earth?

According to the earth science reference tables, during which geologic time period were the continents of north america,south america, and africa closest together?

Name two factors that, "power of magnetic field " of earth.

Alandscaper is shopping for landscaping materials. she wants to use materials through which water flows easily. which materials should she choose? check all that apply. clay gravel granite rocks with cracks loosely packed soil