A 2 kg body undergoes simple harmonic motion of amplitude
10 cm. At this displacement of 10 cm, the restoring force is 20
N. Find the period.

Iron is a transition metal with multiple oxidation numbers. (answer the following) a. what is the iron (ii) ion? how does it differ from the iron (iii) ion? b. if iron were to bond with oxygen, predict the formula for each oxidation number of iron. c. how would each formula be named?