Answer:
Plutonium is the second transuranium element of the actinide series.
Based on the periodic table, the element mendeleev called eka-manganese is now called technetium. Technetium<span> is a silvery-gray metal that tarnishes slowly in moist air. Hope this answers the question. Have a nice day. Feel free to ask more questions.</span>
1) The metal which reduces the other compound is the one higher in the reactivity. So in this case it is
.
2) The substance which brings about reduction while itself getting oxidised (that is losing electrons) is called a reducing agent. Here, $\mathrm{Zn}$ is the reducing agent and reduces Cobalt Oxide to Cobalt while itself getting oxidised to Zinc oxide.
Wym kingdom? I dont get it