Answer:
the H from the HCl switched places with the Fe from the FeS.
1. When sewage treatment plants flood or debris reaches reservoirs and streams, the quality of the water is affected.
2. Storm surges cause beaches to shift and alter shape.
3. During flash floods, riverbanks erode.
All of Dina's potential energy Ep is converted into kinetic energy Ek so Ep=Ek, where Ep=m*g*h and Ek=(1/2)*m*v². m is the mass of Dina, h is the height of ski slope, g=9.8 m/s² and v is the maximal velocity.
So we solve for v:
m*g*h=(1/2)*m*v², masses cancel out,
g*h=(1/2)*v², we multiply by 2,
2*g*h=v² and take the square root to get v
√(2*g*h)=v, we plug in the numbers and get:
v=9.9 m/s.
So Dina's maximum velocity on the bottom of the ski slope is v=9.9 m/s.
The acceleration of the car will be needed in order to calculate the time. It is important to consider that the final speed is equal to zero:

We can clear time in the speed equation:

If you find some mistake in my English, please tell me know.