Suppose the running times of an algorithm for inputs of size 1,000, 2,000, 3,000, and 4,000 are 5 seconds, 40 seconds, 135 seconds, and 320 seconds, respectively, and respond to the following.

1) Estimate how long it will take to solve a problem of size 5,000.

2) Is the algorithm linear, linearithmic, quadratic, cubic, or exponential?

3) Give an explanation of your answer.