$20-$ what will be the static lateral force at ${10}^{th}$ level of structuce if total gravity load is $x$ and portion assighned to the $10th$ level is $10\%.$

$x$

$0\mathrm{.}1x$

$0\mathrm{.}0\mathrm{.}01x$

$-0\mathrm{.}001x$