The picture shows the photo taken by the high-speed camera at the moment when the bullet penetrated Apple. After the photo was enlarged, it was analyzed that the bullet shadow was 5 cm long during the

The picture shows the photo taken by the high-speed camera at the moment when the bullet penetrated Apple. After the photo was enlarged, it was analyzed that the bullet shadow was 5 cm long during the exposure time. Assuming that the front-back distance of the bullet image is about 1.5% of the bullet length,

That is, the actual stagger distance is l = 0.05×1.5% m = 7.5×10-4m,

The exposure time is: t = LV = 7.5× 10? 4500s= 1.5× 10？ 6s，

So the closest is 10-6s, so b is correct.

So choose B.