Answer:
3+6i
Step-by-step explanation:
The area of the shaded sector is one-fourth of the area of the whole circle so:

area of shaded region

The area of the shaded region is 9pi units^2
The GCF of 36 and 81 is 9
36/9 = 4 water balloons
81/9 = 9 beads
Katrina can invite 9 friends, with each getting 4 water balloons and 9 beads
56 because you gotta multiply it