As a result of processing, an industrial plant generates wastewater containing dissolved compounds of copper, tin, and zinc. These metals could be recycled back into production if there was a method to reclaim them from the waste solution. Invent a reclamatory process using single replacement reactions. It should be a detailed paragraph on how you plan on reclaiming the metals out of solution.

the answer is b & c i believe : )

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.