calculate the number of messages per day that each user receives if the number of users is 2586 and the messages per day is 205.6

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

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.

What is the value of m in the equation 1/2 m - 3/4n=16 when n=8