ST and NT denote the standard time and the normal time, respectively, to complete a job. Allowance = LL$\times$ST, where 0 < LL < 1. Which one of the following relationships is correct?
(a) ST = $\frac{NT}{\left ( 1-LL \right )}$ 
(b) ST = NT (1+LL)
(c) ST = $\frac{NT}{\left ( 1+LL \right )}$ (d) ST = NT)1–LL)