How much biomass do we hope to use for energy by 2030? (a)5%
(b)10%
(c)20%
(d)30%

What usually causes a meltdown of a nuclear power plant?
(a)The plant runs out of uranium
(b)Water stops flowing
(c)Too much steam is produced
(d)The reactor catches on fire

Yes it would be a physical change.

The activity series is shown in the attached picture. if the element is below the other, then you can displace the other. following the activity series as a guide, the reactions are as follows: nickel and aluminum chloride3 ni + 2 alcl₃  → 3 nicl₂ + 2 albarium and copper bromideba + cubr  →  no reaction because cu is less oxidizable than bapotassium nitrate and aluminum3 kno₃ + al  → al(no₃)₃ + 3 ksodium phosphate and zincnaso₄ + zn  → znso₄ + na

The answer is c - the principal of original lateral continuity.