Please help with the material science question below, thank you!!

Below is a time$-$temperature transformation diagram for eutectoid composition steel.

a$.$ Describe a heat treatment procedure to create $50\backslash \%$ bainite, $\backslash (50\backslash \%\backslash )$ martensite.

b$.$ Describe a heat treatment procedure to create $\backslash (100\backslash \%\backslash )$ pearlite. Sketch this microstructure.

c$.$ The microstructures in parts a and b consist of ferrite with a density of $\backslash (7\mathrm{.}87\backslash$mathrm$\{$~g$\}/\backslash$mathrm$\{$cm$\}^\{3\}\backslash )$ and cementite with a density of $\backslash (7\mathrm{.}66\backslash$mathrm$\{$~g$\}/\backslash$mathrm$\{$cm$\}^\{3\}\backslash ).$ If a pearlite structure with $400$ nm thick cementite platelets and $1400$ nm thick ferrite platelets is heated to $\backslash (600\{\}^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ for long periods, spheroidite will form. If the resulting speroidite consists of cementite spheres with a diameter of $\backslash (40,000\backslash$mathrm$\{$~nm$\}\backslash )$ in a ferrite matrix, determine the percent reduction in ferrite$/$cementite surface area when the pearlitic steel is spheroidized. Note that the surface area of a sphere is equal to $\backslash (4\backslash$pi r$^\{2\}\backslash ).$

d$.$ Briefly describe the implications of your calculation in part c in terms of how this change in surface area is expected to affect material properties.