You can
put this solution on YOUR website!I'll do the first two to get you started
# 1
)
... Start with the given expression.
}{\log_{10}(9)})
... Use the change of base formula
}{\log_{10}(3^2)})
... Rewrite each term as an exponential expression with a base of 3
}{2\log_{10}(3)})
... Pull down the exponents.

... Cancel out the common terms.
So
)
... Start with the given expression.
}{\log_{10}\left(\frac{1}{4}\right)})
... Use the change of base formula
}{\log_{10}\left(4^{-1}\right)})
... Rewrite each term as an exponential expression with a base of 4
}{-\log_{10}\left(4\right)})
... Pull down the exponents.

... Cancel out the common terms.

... Reduce
So
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Edit: Here's the last solution:
# 3
)
... Start with the given expression.
}{\log_{10}\left(8\right)})
... Use the change of base formula
}{\log_{10}\left(2^{3}\right)})
... Rewrite each term as an exponential expression with a base of 2
}{3\log_{10}\left(2\right)})
... Pull down the exponents.

... Cancel out the common terms.
So