Air flowing parallel to a $20$ m long, $2$ m high, $0\mathrm{.}20$ m thick wall with $\backslash (\backslash$operatorname$\{$Re$\}=4\backslash$times $10^\{4\}*\backslash$mathrm$\{$X$\}\backslash )$ where X is taken from leading edge of wall, $\backslash (\backslash$mathrm$\{$Pr$\}=0\mathrm{.}7\backslash )$; Wall temperature is maintained at $\backslash (\backslash$mathrm$\{$T$\}\_\{\backslash$mathrm$\{$r$\}\}\backslash ),$ while air at T $.$

For each of situation given below give an empirical correlation or equation to calculate Nu $,$ and explain clearly why it is chosen, justification accounts to $\backslash (50\backslash \%\backslash )$ of grade.

a$.$ Heat transfer at the end of wall? $[10]$

b$.$ Heat transfor for the entire wall is required?

$\backslash ([109\backslash )$

c$.$ Heat transfer at a location four meter from leading edge of wall?

d$.$ Heat transfer for the last $4$ meters of the wall? $[10]$

e$.$ Repeat C above if first $2$ m are at air temperature while rest of plate at Ts $.[10]$