(a) “All controllable costs are direct costs. Not all direct costs are controllable.” Explain with the help of suitable examples. (b) Distinguish between (i) engineered, (ii) discretionary, and (iii)...

(a) “All controllable costs are direct costs. Not all direct costs are controllable.” Explain with the help of suitable examples.

(b) Distinguish between (i) engineered, (ii) discretionary, and (iii) committed costs. Give suitable examples. Are all these costs controllable?