Need 19 haven’t a clue on what it is

Layers of rock containing fossils, like the layers illustrated here, are most likely composed of rocks.

Consider the equilibrium system: 2icl(s) ⇄ i2(s) + cl2(g) which of the following changes will increase the total amount of of cl2 that can be produced? all of the listed answers are correct decreasing the volume of the container removing the cl2 as it is formed adding more icl(s) removing some of the i2(s)

The blackbody curve for a star name zeta is shown below. what is the peak wavelength for this star ?