Physics word problem! Help?

Question

A bullet accelerates at 6.9 x 104 m/s2 from rest as it travels the 0.80 m of the rifle barrel. How long was the bullet in the barrel? What was the bullet's velocity as it left the barrel?

Answer 1

a) t=sqrt(2L/a)
t=sqrt(2 x 0.80/6.9 E+4)=
t=4.8 ms

b)v=at
v=6.9 E+4 x 4.8 E-3=330 m/s