Answer
a. $0.072$
b. $0.228$
c. $0.479$
Work Step by Step
The total number is 766
a. Threatened and in the United States
Total threatened and in the United States is 55, $p=55/766=0.072$
b. An endangered foreign bird
Total endangered foreign bird is 175, $p=175/766=0.228$
c. A mammal or a threatened foreign species
Total mammal is 349, P(mammal)=$349/776=0.450$
Total threatened foreign species is 43, P(threatened foreign species)=$43/776=0.055$
P(mammal and threatened foreign species)=$20/776=0.026$
P(mammal or threatened foreign species)=$0.450+0.055-0.026=0.479$
