Energy in Steady Flow

Problem $2$

In the pipe: $h_L=1\mathrm{.}6\frac{V^2}{2}g$

$p_{\text{a}\text{t}\text{m}}=90$kPa

For the liquid in the suction pipe, $V=1\mathrm{.}8\frac{m}{s}$

What is the maximum allowable value of $z$ if the liquid were

a$)$ Water at $20C$

b$)$ Gasoline with $p_v=49$kPa abs with a specific weight of $8k\frac{N}{m^3}$