What is the main incentive for using a command economy?

Why would the crystals in an intrusive igneous rock be larger than the crystals in a chemical sedimentary rock? a. intrusive rocks form beneath the earth's surface, so they cool very slowly, which produces larger crystals. b. chemical sedimentary rocks form from dissolved substances on the earth's surface with very high heat and cool very slowly, which produces smaller crystals. c. chemical sedimentary rocks and intrusive rocks have crystals of the same size. o d. chemical sedimentary rocks form deep in the earth, so they cool slower, which produces small crystals. € read question correct:

In 2002, north korea announced that it was shutting down its nuclear facilities constructing a hydroelectric energy plant restarting nuclear weapon development changing to a free market economy

The percentage of people in the united states engaged in agriculture in 2000 was approximately a. 56% b. 38% c. 21% d. 2%