Problem $5$: Gasoline is piped underground from refineries to major users. The flow rate is $3\mathrm{.}00{10}^{-2}\frac{m^3}{s}($about $500ga\frac{l}{m}in),$ the viscosity of gasoline is $1\mathrm{.}00{10}^{-3}(\frac{N}{m^2})*s,$ and its density is $680k\frac{g}{m^3}.($a$)$ What minimum diameter must the pipe have if the Reynolds number is to be less than $2000?(2\mathrm{.}5$pt$)$

B$)$ what pressure difference must be maintained along each kilometer of the pipe to maintain this flow rate?

Please answer both parts a and b