The height in meters of a lava rock that falls for 5 seconds is; 122.5 m.
We are told that the height is modelled by the equation;
y = ยน/โgtยฒ
where;
y represents the height.
g is 9.8 m/sยฒ
t represents the falling time of the lava rocks.
Thus, at t = 5, we have;
y(5) = ยน/โ(9.8)(5)ยฒ
y(5) = 122.5 m
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