Three traffic lights at three different road change after 48seconds ,72seconds, and 100 seconds respectively if they change simultaneously at8:00am at what time will they change simultaneously respectively

Can any one me with the answers to these questions asap?

1jessica's home town is a mid-sized city experiencing a decline in population. the following graph models the estimated population if the decline continues at the same rate. select the most appropriate unit for the measure of time that the graph represents. a. years b. hours c. days d. weeks

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.