What is load line and operating point of a transistor

Different types of steels contain different elements that alter the characteristics of the steel. for each of the following elements, explain what the element does when alloyed with steel.

Hydraulic fluid with a sg. of 0.78 is flowing through a 1.5 in. i.d. pipe at 58 gal/min. the fluid has an absolute viscosity of 11.8 x 105 lbf-sec/ft2. is the flow laminar, turbulent or within the critical range? give both a numerical reynolds number and a term answer.

What is the main objective of using reheat rankine cycle?