A helium balloon on a string is tethered to a fence outside of a house. The altitude of the balloc be represented by the rational number feet. The string breaks and the balloon ascends 20 feet minute for 5 minutes. The helium then begins to leak out of the balloon, causing it to descend a per minute for 4 minutes. What is the elevation of the balloon after it descends for 4 minutes?​

Using pert, adam munson was able to determine that the expected project completion time for the construction of a pleasure yacht is 21 months, and the project variance is 4. a) what is the probability that the project will be completed in 17 months? b) what is the probability that the project will be completed in 20 months? c) what is the probability that the project will be completed in 23 months? d) what is the probability that the project will be completed in 25 months? e) what is the due date that yields a 95% chance of completion?