A jet and a light plane leave from the same airport at the same time and travel in opposite directions, one at 500 km/h and another at 700 km/h. They will be 3600 km apart in:
4 hours.
6 hours.
12 hours.
None of these choices are correct.

Me its important ! marge runs an ice cream parlor. her speciality is triple chocolate sundaes.she can prepare 1 sundae every 2 minutes, and she earns $1.20 for each sundae she makes . if she just makes sundaes for a single shift of at most 4 hours and at least 2 hours , which function relates her earnings to the number of minutes she works?