The following contingency of frequencies is based on a 5-year study of fire fatalities in Maryland. For purposes of clarity, columns and rows are identified by the letters A-C and D-G, respectively.

Blood Alcohol Level of Victim
A B C
Age 0.00% 0.01-0.09% ¡Ý0.10%
D 0-19 142 7 6 155
E 20-39 47 8 41 96
F 40-59 29 8 77 114
G 60 or over 47 7 35 89
265 30 159 454+
a. For this table, identify any two events that are mutually exclusive.
b. For this table, identify any two events that interest.