Acceleration= change in speed/time.
Acceleration = 70,000 m/s / 7 sec.
Acceleration = 10,000 m/s^2
This is an absurd claim. It's obviously a misprint, and nobody who sees it will believe it.
As soon as you give it the gas, the car would cover 3 miles in one second, and any thing or any body riding in that car would pull more than 1,000 G's !
Our technology has no way to produce acceleration like that. But if we could, the car and its driver would be instantly torn apart !