$($b$)$ Pran Candy makes candy bars for vending machines and sells them to vendors in cases of $30$ bars. Although Pran Candy makes a variety of candy, the cost differences are insignificant, and the cases all sell for the same price.

Pran Candy has a total capital investment of Tk$.15,000,000.$ It expects to produce and sell $300,000$ cases of candy next year. Pran Candy requires a $10\%$ target return on investment. Expected costs for next year are:

$\backslash$table$[[$Variable production costs,Tk$.4$ per case$],[$Variable marketing and distribution costs,Tk$.1$ per case$],[$Fixed production costs,Tk$.300,000],[$Fixed marketing and distribution costs,Tk$.400,000],[$Other fixed costs,Tk$.200,000]]$

Pran Candy prices the cases of candy at full cost$-$plus markup to generate profits equal to the target return on capital.

Required:

$($i$)$ What is the target operating income?

$($ii$)$ What is the selling price Pran Candy needs to charge to earn the target operating income? Calculate the markup percentage on full cost.

$($iii$)$ Pran Candy's closest competitor has just increased its candy case price to Tk$\mathrm{.}16,$ although it sells $36$ candy bars per case. Pran Candy is considering increasing its selling price to Tk$.15$ per case. Assuming production and sales decrease by $4\%,$ calculat$$ Pran Candy's return on investment. Is increasing the selling price a aood idea?