Answer:
MAD:  10.04,  11.53
MAPSE: 10% ,  12%
MSE : 146.33,  178.72
Bias : -0.56 , -0.96
3-week moving average method is better
Explanation:
i ) Evaluate MAD ( average of absolute errors )
using  3 week moving average 
= 10.04 
using simple exponential smoothing
= 11.53
ii) MAPSE ( average of absolute percentage error ) 
 using 3 week moving average 
= 10% 
using simple exponential smoothing
 = 12% 
iii) MSE ( average of Squared Errors )
3 week MV = 146.33 ,  Simple exponential smoothing = 178.72. 
iv) Bias
3 week MV = -5/9 = -0.56,  Simple exponential smoothing = -8.69/9 = -0.96.
v) TS  ( Total error / MAD )
3 week MV = -5 / 10.04 = -0.49 , 
simple exponential smoothing  = -8.69 / 11.53 = -0.75
b) I prefer 3-week moving average based on the values of MAD , MAPE, MSE, bias and TS which shows that there is a better estimate when using the 3 -weeks moving average.
Attached below is the Tabular calculations of the required parameters for the  question