A boson notated with this letter is the weak hypercharge gauge boson and can mix with W3 to form the Z boson and photon. A set (15[1])of four mesons symbolized by this letter includes the (15[1])heaviest [emphasize] charged (-5[1])meson, as well as the heaviest neutral mesons to undergo matter-antimatter oscillations. (-5[1])A quantum number represented by this letter equals one-third of the quantity number of quarks minus the number of antiquarks, and is conserved in the Standard Model (15[1])along with (*) L. The upsilon (10[1])meson is made (-5[1])up of a quark of this letter paired with its (-5[1])antiquark. Yellow is the (-5[1])anticolor of this color state, the alphabetically first of (10[1])three. This letter represents the (10[3])second-heaviest (10[2]-5[2])quark, which is (10[1])paired with the top (10[3])quark (10[1])in the (10[1]-5[1])third (10[2]-5[3])generation. For 10 (10[3])points, name this (10[1])letter which, along with (10[1])r and (10[3])g, (10[4])constitutes (10[3])color (10[5])charge. (10[10])■END■