Can someone tell me the right answer pls and you

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters

An entertainment firm offer serveral dj choices and light shows that range in price based on the rental time period. the djs cost between $219 and $369 per night and the light shows cost between $159 and $309 per night. if you are booking both a dj and a light show write a compound inequality that represents the possible total amount you would pay x