What are two ways to classify a compound in science

The first-order reaction a→2b+c has rate constant 0.538 s−1. if the initial concentration of a is 0.867 mol l−1, what is the half-life of the reaction in seconds? remember to use correct significant figures in your answer (round your answer to the nearest hundredth). do not include units in your response.

Where should a carbon monoxide detector be mounted?

An impulse is the product of the on an object and time during which it is applied