Convert the following:

a$.$ Convert into SI units $(N*m)$ a torque defined by a $210lbf$ force applied $8$ in from the axis of rotation.

b$.$ Convert $78k\frac{m}{h}$ to $k\frac{m}{s}.$ How many $f\frac{t}{h}$ is this?

For a tatic's problem your calculations show the final answer as $12345\mathrm{.}6N.$ What will you write as your final answer? Explain your answer.

A$)12345\mathrm{.}6N$

B$)12\mathrm{.}3456kN$

C$)12kN$

D$)12\mathrm{.}3kN$

E$)123kN$