Why is fluted filter paper used in gravity filtration?.

Can anybody me with this? ? (picture included.)

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.

The frequencies refer to the sample data collected from a population of interest when performing a hypothesis test comparing two or more population proportions.