$2(20$ points$)$: Atmospheric tank $($i$.$e$.,$ not under pressure$)$ containing an

We substance. The tank is supported on four legs. $S_S=1\mathrm{.}65$ and $S_1=0\mathrm{.}95.$

teight of empty tank is $10$ kips. Weight of contents is $50$ kips. Natural period of

profile.

Determine: The maximum design horizontal seismic force when the tank is

supported on the roof of a ten$-$story hospital building.