What is the age of an intrusion of igneous rock in relation to the sedimentary rock layers through which it passes?

always older
always younger
sometimes younger, sometimes older
the same age as the other rock layers

What is the mercury length of time for one revolution around the sun?

Which of the following insects is a decomposer? a. mosquito. b. caterpillar. c. beetle. d. none of the above.

1. crust 1 the metallic layer at the earth's center 2. inner core 3 the firm layer between the crust and the asthenosphere 3. lower mantle 2 the layer surrounding the inner core 4. asthenosphere 4 the semi-solid layer between the top layer and the upper mantle 5. upper mantle 5 the layer between the asthenosphere and lower mantle 6. top layer 6 the earth's outermost layer 7. outer core 7 the hottest part of the mantle