Time=speed/acceleration
Gravitaional Acceleration=9.8 m/s^2
Speed=24.5 m/s
Time=24.5/9.8=2.5 s
here's the first part but for the 2nd one all I know is that the word "compression" goes on the spirals that are closer together.
hope this helps!
the first step would be gathering information , and making sure its correct
C, Since binary ionic compound is only of 2 elements. Mg is ionic and so i F so thats it. H20 is covalent B is more than 1 element, D looks dodgy, nah its dat ionic compunds wouldnt form big ones like SF (6)