What borders mexico on all four sides

Gemstones are commonly found in pegmatites, which are igneous rocks that are a. exceptionally mafic b. exceptionally coarse grained c. exceptionally fine grained d. extrusive, forming from lava

Suggest two reasons why irrigation is important for human development of the desert (4 marks)

[ou.01jthe greatest speed with which any physical object moves is 300,000 km/soundsec. which of the following has a speed of 300,000 km/sec? a.light in water b.light in vacuum c.sound in air. d. sound in water