Igneous rocks choose one: a. form only at the earth's surface. b. are coarse-grained if they cool extrusively. c. form from the addition of heat and pressure to a pre-existing rock. d. were the first rocks to exist on the earth.

Which of the following statements best characterizes changes to agriculture in the united states since 1900? a. increased mechanization has reduced the need for labor. b. increased mechanization has increased the need for water, thereby increasing the need for labor. increased mechanization has increased the use of land, thereby increasing the need for labor. d. increased mechanization has increased food production, thereby increasing the need for labor. select the best answer from the choices provided.

Chris lives in a city that experiences heavy rainfall with average annual precipitation of 882 millimeters. it is warm all year. mark lives in city with an average annual rainfall of 40 millimeters. it has hot summers and cool winters. chris's city is in a climate, while mark's city is in a climate.

The movement of which layer of earth drives the motion of the plates on earth's crust