Answer:
40km/hr
Explanation:
Speed = Distance ÷ Time and since they both have different units we have to change one of them. Therefore if we change 30 minutes to half an hour we say 20km ÷ ¹/2
Answer:
c) +2 to 0
Explanation:
SO4 has a charge of -2, so the Cu attached to that has to be a +2 since the polyatomic molecule has no overall charge
Cu(s) is a solid metal and they have no charge, therefore it is zero
Copper undergoes Oxidation (gain of electrons)
Answer:
Enzyme.
Explanation:
Enzymes act as a catalyst in all reaction but remain unchanged by the process.
Since the atomic number of calcium is 20. The number of protons is also 20.
The answer is B or the second answer