What are two different ways to tell time

This image is an example of a(n) a) atom. b) compound. c) mixture. d) molecule.

Ais a mountain created from eruptions of lava, ash, rocks, and hot gases.

The rate constant for the reaction below is 6.2 x 10−5 mol l−1 s −1. if the initial concentration of a is 0.0500 m, what is its concentration after 115 s?