Rewrite the equation $4^2=16$42=16 in logarithmic form (with the index as the subject of the equation).
Rewrite the equation $9^x=81$9x=81 in logarithmic form (with the index as the subject of the equation).
Rewrite the equation $4^1=4$41=4 in logarithmic form (with the index as the subject of the equation).
Rewrite the equation $3^0=1$30=1 in logarithmic form (where the index is the subject of the equation).