Please reply with MatLab/SciLab code

The Taylor series for e^-x around x = l is: e^-x = e^-1 - e^-1 (x - 1) + e^-1/2! (x - 1)^2 - e^-1/3! (x - 1)^3 + ellipsis. a) Write the kth expression of the Taylor series in Matlab notation b) Write a "for" loop to compute e^-x using the first 20 expressions of its Taylor series. c) Output the result in fixed point format, with 4 digits after the decimal point