Centered around hudson bay in north america and extending to greenland, the shield is composed of precambrian rocks that cover 2.8 million square miles.

As water is cooled from 4 c to 0 c its density

Some gamma ray bursts are hypothesized to come from mergers of neutron stars or black holes. if this hypothesis is correct, what else should we in principle be able to detect from such mergers? a. gravitiational waves b. x-ray bursts c. significant disruption of gas thousands of light-years away in the surrounding galaxy d. an "afterglow" of bright visible light, lasting for weeks

Why did the united states lead a coalition to invade iraq in 1991? o a. there was a fundamentalist revolution in iraq. o b. iraq had invaded iran. o c. an oil embargo had started in the middle east, o d. iraq had invaded kuwait.