The figure below shows a quadrilateral abcd with diagonal bd bisecting angle adc:

a quadrilateral abcd is drawn with bd as a diagonal. bd bisects angle adc and forms two triangles abd and cbd. ab and cb are equal in length. (i attached a picture to the question).

which equation is true?
a) db = 2dc
b) ad = dc
c) ab = db
d) ab = 2ad

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?