PLEASE LOOK at the photo and help me on these 2 questions :(

Determine if the sequence is geometric. if it is, find the common ratio. 1) -2, 2/3, -2/9, 2/27 2) 0,2,5,9 3) 2, -10, 50, -250 4) 1,4,16,64

An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is