Tolong di jawab kak nanti aku follow deh

A. KMnO4
= 1×biloks K + 1×biloks Mn + 4×biloks O = 0
= (+1) + Mn + 4×(-2) = 0
= (+1) + Mn + (-8) = 0
Mn = 8-1
Mn = +7

b. SO4^2-
= 1× biloks S + 4×biloks O = -2
= S + 4×(-2) = -2
= S + (-8) = -2
S = -2 + 8
S = +6

c. K2Cr2O7
= 2×biloks K + 2×biloks Cr + 7×biloks O = 0
= 2×(+1) + 2Cr + 7×(-2) = 0
= (+2) + 2Cr + (-14) = 0
2Cr = 14-2
2Cr = +12
Cr =12/2
Cr = +6