Delta Sonic is a car wash provider in Western New York. VIP Customers at their Buffalo, NY location sign up for unlimited car washes and a separate line & dedicated car wash services those customers (i.e. a single-server single-queue model). Assume VIP customers arrive every 12 minutes on average and that their inter-arrival time is exponentially distributed. Assume that the standard processing (washing) time is the sum of two components: A constant (i.e. not random) basic washing time that is exactly 4 minutes. A random extra-service time that is normally distributed with mean time of 4 minutes and standard deviation of 1 minute. In addition, assume that 50% of customers opt for an additional tire shine service that adds an exponentially distributed amount of service time with mean of 2 minutes. In Excel, simulate the arrival times and processing times of VIP customers at this car wash using 100,000 sample customers. Using the results of your simulation, calculate the percentage of VIP customers that were in the process (i.e. waiting+washing+extra services) for longer than 15 minutes. Press F9 to rerun your simulation several times and record the results for the percentage of customers who wait longer than 15 minutes. Using the median of these recorded percentages as your estimate of the percentage of customers expected to wait longer than 15 minutes, enter that probability here as a three digit decimal e.g. 0.256, 0.452, 0.991, etc.) Hint 1: "=if(rand()>0.5,1,0)" can be used to simulate whether the customer opts for the additional tire shine. Hint 2: "=NORM.INV(RAND(),15,2)" can be used to simulate a normally distributed random variable with mean of 15 and standard deviation of 2.