Pre$-$stressed Connete

$(1)$ A post$-$tensioned pretlressed beam of rectangular section $300mm$ cuide to be derigned for an imposed load of $15k\frac{N}{m},$ uniformly distributed on a lpan of $12m.$ The etress in lere concrete nust not exceed $17\frac{N}{m}{m}^2$ in comp ression $0r,1\mathrm{.}5\frac{N}{m}{m}^2$ in tension at any time and loss of prestress may be assumed to be $17\%.$

calculate $(1)Hi{n}^m$ possible depth of the beam.

$(2)$ forthe section proinded,

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