How do you find the explicit and recursive formulas for a geometric sequence?

The amount of energy it takes to lift a box might be a function of which of the following

What is the value of x? enter your answer in the box. photo attached.

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.