error reading using xlsread

I am trying to run this code and i am getting an error 'Undefined operator '.*' for input arguments of type 'cell'. All i am trying to do is vector multiplication of the two columns of data which is imported from the file.

clc
clear all
[num,txt,Rawdata] = xlsread ('MAE 525 HW5 Soln.xlsx'); 
CO2_meas = Rawdata (16:end,2);
CO_meas = Rawdata (16:end,3);
result = CO2_meas.* CO_meas

Answer 1

[Azzi Abdelmalek]

[num,txt,Rawdata] = xlsread ('MAE 525 HW5 Soln.xlsx'); 
CO2_meas = num(16:end,2);
CO_meas = num(16:end,3);
result = CO2_meas.* CO_meas