Answer
$26\frac{m}{s^2}$
Work Step by Step
We can find the required acceleration as follows:
$\Sigma F_y=\mu_sN-mg=0$
$\implies N=\frac{mg}{\mu_s}$
Now the horizontal component of force is given as
$\Sigma F_x=N$
$\implies ma=N$
$\implies a=\frac{N}{m}$
$\implies a=\frac{\frac{mg}{\mu_s}}{m}$
This simplifies to:
$a=\frac{g}{\mu_s}$
We plug in the known values to obtain:
$a=\frac{9.81}{0.38}$
$a=26\frac{m}{s^2}$