An elevated storage tank discharges water $(T=30C)$ through an outlet $(C_d=0\mathrm{.}85)$ to a very short length of $400-mm$ diameter ductile iron pipe, which discharges a free jet for a construction project. If the required flow rate is $1\frac{m^3}{sec},$ calculate required water depth above tank outlet using the Bernoulli equation $($assume $K_{\text{o}\text{u}\text{t}\text{l}\text{e}\text{t}}=0\mathrm{.}25)$and the free jet equation.

Estimate pressure $(kPa)$ at storage tank outlet in Problem No$.4$ using either depth.

Determine required pipe size for Problem No$.4$ if the flow rate increases to $2\frac{m^3}{sec}$ and all other conditions remain the same$-$use both equations to size pipe.