It really is not as hard as it seems. One of the key skills needed to be successful on the science portion of the ACT is the ability to read and interpret graphs and tables. Graphs always represent the relationship between sets of data, ususally two sets of data, but sometimes it can be more than two. For example, the graph may show a trend in a population over a time period such as the amount of electricity used over a period of years. It's your job to note trends over the time period. Tables usually contain both quantitative and qualitative information, so understanding why both sets of data are important will help you to answer the questions on the test that require you to analyze that data. Take the time to look over the graphs and tables BEFORE you jump to the questions. This makes answering the questions so much easier since you have an understanding of the data and hence know where to go to find the answer.