Question

eview the abstract and then answer the question.
gravity and drag both reduce the maximum altitude that a rocket can reach, increa
the cost of rocket flights. this study hypothesizes that rockets with a smoother sur
will experience less drag and reach higher altitudes, given the same thrust as rocke
with rough surfaces. to test this hypothesis, three identical model rockets were
constructed and given finishes with varying degrees of surface smoothness: roughe
40 - grit sandpaper, unfinished, and glossed. each rocket was outfitted with b5 - 4 mo
and flown ten times. flight results support the initial hypothesis, with the roughene
surface rocket reaching the apogee point at the lowest altitude and the glossed - sur
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 potenti
increasing rocket efficiency and reducing fuel costs.
what is the texts main purpose?
to promote high gloss surfaces
to motivate readers to fly model rockets
to inform readers about an experiment

Explanation:

The text presents a hypothesis about rocket surface smoothness and drag, describes an experiment (three rockets with different surface finishes, same thrust, multiple flights), and shares results. It's focused on communicating the experiment details rather than promoting a product (like high - gloss surfaces) or motivating model rocket flight.

Answer:

to inform readers about an experiment