Answer
seven;
$10,000,000$
Work Step by Step
RECALL:
$10^n$ is equal to $1$ followed by $n$ zeros.
Thus,
$10^7$ is equal to $1$ followed by seven zeros.
In symbols,
$10^7=10,000,000$
Thus, the missing expressions in the given statement (in order) are:
seven;
$10,000,000$