Halo 3 Questions?

[««{¿Âúzï Ë!¡!™?}»»]

Spartan laser double kill- Can you get it by destroying a vehicle with people inside?

Terminals, I got all terminals like 5 times and still ddin't get the acheivement?

how do i get the "Security" Helmet?

 

[zomo]

ill help you out on the one i know laser kill yes you can
get it when you kill 2 people in the car and if theres there
you can get the used car salesman achevment!

 

[christoogood4u]

yea i pwn with spartan laser but i cant aim it if not zoomed and they right next to me, otherwise i can hit a moving target easily and can u get the acheivment on player matches cause i got 2 kill with laser when they were in warthog