A small quantity of radioactive gold was deposited on the end of a gold cylinder After holding for 24 h at a high temperature the specimen was sectioned and the radioactivity of each slice was as follows: Distance from end of to center of slice (um) 10 20 30 40 50 bar Radioactivity (a. u.) 83.8 66.4 42.0 23.6 8.74 Use the above data to determine the diffusivity D).

Rocks, as they are compressed, begin forming mountains above the earth's surface when two continental plates converge. the continental crust increases in depth as the mountains grow above. the himalayan mountains formed at a convergent plate boundary in this manner. the rocks are smashed together causing them to due to the intense heat and pressure from the colliding plates and eventually forming rock. a) melt; igneous b) layer; sedimentary c) recrystallize; metamorphic d) melt into the earth's interior; metamorphic