A skydiver jumps from a helicopter hovering at high altitude. if there were no air resistance, how fast would she be falling 12s after jumping?

Well, if there were no air resistance, then a helicopter couldn't fly. But let's do the physics and the Math anyway:

The way gravity works, the speed of a falling object increases at the rate of 9.8 m/s every second.

So, after falling for 12 seconds, its speed is (12 x 9.8) = 117.6 m/s.