Help me find the length of the missing sides numbers 1 - 6 will give you 30 points

Acircular city park has a sidewalk directly through the middle that is 111 - feet long. if each bag of fertilizer covers 50 square feet, then determine how many bags of fertilizers the parks and recreation department needs to use to cover the circular park. ignore all the sidewalks around and through the park.

Anyone know? will mark brainliest if correct

Solve the system of equations using the substitution method. {y=−3x+7x=−2y−16 enter your answers in the boxes.