I have a quiz yall help

How many moles are in a 18 L tank of nitrogen gas at STP?

If a plot weight (in g) vs. volume (in ml) for a metal gave the equation y= 13.41x and r^2=0.9981 what is the density of the metal?

For the following dehydrohalogenation (e2) reaction, draw the zaitsev product(s) resulting from elimination involving c3–c4 (i.e., the carbon atoms depicted with stereobonds). show the product stereochemistry clearly. if there is more than one organic product, both products may be drawn in the same box. ignore elimination involving c3 or c4 and any carbon atom other than c4 or c3.

Which type of fossil does this image depict?