Polar bears give birth to to club per litter, every three years - what type is the survivorship curve

Robert wants to know which fertilizer will work the best for his grass. what can he do to explore this inquiry?

Which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements.which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements.the framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center.because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane.the diverse proteins found in and attached to membranes perform many important functions.the kinky tails of some proteins keep the membrane fluid by preventing the component molecules from packing solidly together.membranes include a mosaic, or mix, of carbohydrates embedded in a phospholipid bilayer.

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?