Which information is necessary to solve this story problem?
there were 16 people at a backyard barbeque. the barbeque lasted for 4 hours. barry bought 2 hot dogs for each person. each hot dog cost $1.25. how much did barry spend altogether?
a.
2 hot dogs, 16 people, $1.25
b.
4 hours, 16 people, 2 hot dogs
c.
2 hot dogs, 16 people
d.
2 hot dogs, $1.25

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?