This is the most common instrument that hammer-ons [“hammer on’s”] can be played on.  This instrument can produce natural harmonics if players lightly rest one finger on its fifth fret. (*) Rock musicians usually use a triangular pick to play—for 10 points—what six-stringed instrument that can be strummed? 

Analysis of these organisms is the focus of dendrochronology [DEN-droh-kruh-NAHL-uh-jee].  Ecosystems created by these organisms may be divided into emergent, understory, and (*) canopy layers.  Growth rings can be counted on the cross-sections of the trunks of—for 10 points—what plants, such as conifers, that create forests?