4. Composite random variables (20 marks). Let X be a Gaussian random variable with mean 100 and standard deviation 3. Let Y also be a Gaussian Random variable with mean 150 and standard deviation 5. The composite random variable Z(t) is defined as, Z(t)=Xcos(2t)+Ysin(2t). Steps: a. Create a linearly spaced row matrix of time indexing 0 to 100, using the linspace command. b. Generate the Gaussian random variables X and Y with their corresponding parameters using the rand command. Note that, in MATLAB exercise 2_1, we created an array of Gaussian variables, but here we need to create only one Gaussian variable from each Gaussian distribution. c. Plot the random process Z(t). d. Using the command mean, determine the expected value of Z(t)