How many theoretical plates produce a chromatography peak eluting at 12.83 min with a width at half-height of 8.7 s

Which of the following true? a_volcanoes and earthquakes often near the plate boundaries. b_volcanoes occur whereve there are tall mountains. c_earthquakes cause volcanoes in the same location to erupt violently d_volcanoes and earthquakes occur only where plates are colliding with each other

Particles vibrate in a rigid structure and do not move relative to their neighbors.

What metric units would you use to measure the thickness of a key