A $3\mathrm{.}1-$liter SI engine is to be designed with a central spark plug and combustion at TDC$,$ this gives a flame travel distance of B$/3.$ The engine is to operate with an average piston speed of $9$ m$/$sec and a burn angle of $22$ of engine crank rotation. Stroke and bore will be related by S $=0\mathrm{.}9$B$.$ Calculate: $($a$)$ Draw a cross section of the engine cylinder and locate the position of the spark plug $($a$)$ Average flame speed in $($m$/$s$)$ if the design is for an in$-$line four$-$cylinder engine. $($b$)$ Average flame speed in $($m$/$s$)$ if the design is for a V$8$ engine.