There is a coating on the feathers of waterfowl such as ducks that keep them from getting wet when in water. What molecule would this water-repelling coating be made of

Which of the rock examples below is most likely to be metamorphic

Zoe decided to measure the hand length of each of her classmates. first she marked a line across each student's wrist and lined up a ruler from this mark to the top of the middle finger to measure the length. then she recorded the measurements in the table below. marla did this the same way for each classmate, and then zoe used this ruler to measure each straight line and record the data below. this data is invalid. what is the most likely reason why it is invalid? the ruler is marked in centimeters, but zoe recorded data in inches. the range of lengths is too wide, so zoe must have misread the ruler. marla’s complicated measuring procedure was overly confusing. marla could have been inconsistent while drawing outlines of fingers.

Spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?