Final answer:
The equation that can be used to find the number of bacteria, y, after x hours is y = 300(2^x).
Step-by-step explanation:
The equation that can be used to find the number of bacteria, y, after x hours is option B) y = 300(2^x). This equation represents exponential growth, where the number of bacteria doubles with each passing hour. For example, after 1 hour (x=1), the equation would be y = 300(2^1) = 600. After 2 hours (x=2), it would be y = 300(2^2) = 1200.