1. Write a MATLAB code for a function that takes variable numbers as input and output sum of these input. [5] 2. For a cell array, A={magic(5), magic(10), magic(15)}; find the diagonal entries of matrix in each cell. [5] 3. Write MATLAB code (also plot) the following equations. [10] [1, t= 3 i, t> 5 (i) f(t) = (ii) f(t) = t#3 t a (iii) f(t) (iv) f(t) = 0 t-a 10 sin(at) t+0, (v) f(t) = t=0. t 15. 5. For the message signals given below: [20] (i) A1 sin 27 fit (ii) A2 cos 21 fat Find and plot: (1) amplitude, phase and frequency modulated signals. (2) Fourier transform of (i), (ii) and (1). (3) Power spectral density estimate of (i), (ii) and (1). Note: Mention your choice of A1, A2, fi, f2, fc, kf, kp, frequency and phase deviations. In plots of Fourier transform/power spectral density, x-axis should not be in terms of frequency bins