If a space probe moves 20 m in 4 s, how fast is it moving?

Aknife blade is a(n) a. lever b. screw c. wedge d. inclined plane

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?

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?