A group of friends is addressing wedding invitations. Casey can address 22 envelopes in one hour, Anne can address 46 envelopes
in two hours, and Paula can address 70 envelopes in three hours. About how long will it take them to address 450 envelopes? A. 19.57 hours
B. 23.00 hours
C. 7.34 hours
D. 6.59 hours