Question

read the abstract and then answer the question.
gravity and drag both reduce the maximum altitude that a rocket can reach, increasing the cost of rocket flights. this study hypothesizes that rockets with a smoother surface will experience less drag and reach higher altitudes, given the same thrust as rockets with rough surfaces. to test this hypothesis, three identical model rockets were constructed and given finishes with varying degrees of surface smoothness: roughed with 40 - grit sandpaper, unfinished, and glossed. each rocket was outfitted with b5 - 4 motors and flown ten times. flight results support the initial hypothesis, with the roughened - surface rocket reaching the apogee point at the lowest altitude and the glossed - surface rocket reaching it at the highest. in conclusion, the findings suggest that smoother surface finishes can reduce the drag force enough to affect altitude, thereby potentially increasing rocket efficiency and reducing fuel costs.
who is the primary audience?
high school math students
people concerned about the price of gas
academics in the field of engineering
model rocket hobbyists

Explanation:

The study involves rocket design, aerodynamics (drag), and engineering - related concepts (efficiency, fuel costs). High school math students would likely not focus on such technical rocket - engineering aspects. People concerned about gas prices are more related to general fuel costs in daily life (like for cars) rather than rocket - specific fuel efficiency. Model rocket hobbyists might be interested, but the academic and engineering - focused language (hypothesis testing, technical descriptions of rocket surfaces) points more towards academics in engineering. Engineering academics would be interested in the technical analysis of how surface smoothness affects rocket performance (drag, altitude, efficiency), which is a core engineering topic.

Answer:

academics in the field of engineering