State the type of reaction and balance the reactions. basically fill in all the blanks

Explanation:

Na2S + Zn(NO3)2  ⇒  2 NaNO3 + ZnS      Double displacement reaction

6 Li + N2  ⇒   2 Li3N                                   Synthesis reaction

2 KClO    ⇒   KCl + O2                                Decomposition reaction

CH4 + 2 O2   ⇒   2 H2O   + CO2               Single displacement reaction

Mg   +   2 AgNO3   ⇒   Mg(NO3)2     +   2 Ag     Single displacement reaction

i think it would be 80 km/h because 30 + 50 = 80 (sorry if this not the right answer i'm trying my best)