I want an answer not a like that don't work!!

3.4a=57.8 what is the the value of a

Which of the following is a cost homeowners insurance does not protect? a. the cost of repair or replacement of a home lost in a natural disaster. b. additional living expenses required while your home is repaired after a disaster. c. replacement costs for all contents in your home, including high cost electronics. d. the cost of medical expenses incurred by somebody getting injured on your property. select the best answer from the choices provided

Which situation is an example of an observational study?