How do whales bats and dolphins use echolocation?

a to scare away predators
b to attract mates
c to orient them selves and find food
d to tell animals of there species where they are

Adisk with a radius of r is oriented with its normal unit vector at an angle q with respect to a uniform electric field. which of the following would result in an increase in the electric flux through the disk? check all that apply? a. increasing the area of the disk b. decreasing the given orientation angle of the disk c. decreasing the strength of the electric field d. increasing the given orientation angle of the disk, but not exceeding an angle of 90