WILL GIVE AND 30 POINTS

Please tell me which one connects to which

Question: what is the value of x 4x-2= (-7) +5x. it would be greatly appreciated if someone could actually explain to me step by step

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.