Macy always thought there were only a few hair colors: blond, brown, and black. however, when she actually began looking around, she saw varying shades of these hair colors. what is a possible reason for so many different hair colors?

codominance

coinheritance

incomplete dominance

incomplete inheritance

polygenic inheritance

Cyclotrons are widely used in nuclear medicine for producing short-lived radioactive isotopes. these cyclotrons typically accelerate h- (the hydride ion, which has one proton and two electrons) to an energy of 5 mev to 20 mev. this ion has a mass very close to that of a proton because the electron mass is negligible—about 1 2000 of the proton’s mass. a typical magnetic field in such cyclotrons is 1.9 t. (a) what is the speed of a 5.0-mev h-? (b) if the h- has energy 5.0 mev and b = 1.9 t, what is the radius of this ion’s circular orbit?