Problem $4$: Complete the following statements correctly:

$($a$)$ Along a streamline the value of is constant.

$($b$)$ The velocity vector can be found by differentiating $\backslash (\backslash$phi $\backslash )$ in the direction as the velocity.

$($c$)$ Streamfunctions can be defined for a flow that is

$($d$)$ To define a velocity potential a given flow must be

$($e$)$ In $2-$D flow, the equation for a streamline is

$($f$)$ List the assumptions necessary to use Bernoulli's equation for a given flow:

$(1)$

$(2)$

$(3)$

$(4)$