After 4797 y, how much of an original 0.250 g sample of radium-226 remains? Its half-life is 1599 y.

In the following redox reaction which is the oxidizing agent and which is the reducing agent? alcl3 + na nacl + al

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

Which of the following best describes technology a. something created for only scientists to use b.the method of thinking that scientists use. c.the application of engineering to create useful products. c. a scientific idea