Answer
One
Work Step by Step
We know that
$m=\frac{1}{N\lambda_{max}}$
We plug in the known values to obtain:
$m=\frac{1}{(7600cm^{-1})(\frac{100cm}{1m})(700\times 10^{-9}m)}$
$m=1.87$
The value of $m$ is less than 2. Thus, we have only one complete visible spectrum formed on either side of the central maximum.