One central idea in “Mars Terraforming Not Possible Using Present-Day Technology” is that there is not enough carbon dioxide in Mars’s soil and rocks to make the atmosphere habitable. Which details from the text support this idea?
There is more than one answer.

Just using the deposits near the surface would require extensive strip mining, and going after all the CO2 attached to dust particles would require strip mining the entire planet to a depth of around 100 yards.

The most accessible source is CO2 in the polar ice caps; it could be vaporized by spreading dust on it to absorb more solar radiation or by using explosives.

Using the recent NASA spacecraft observations of mineral deposits, the team estimates the most plausible amount will yield less than 5 percent of the required pressure, depending on how extensive deposits buried close to the surface may be.

With Mars being further away from the sun, researchers estimate a CO2 pressure similar to Earth’s total atmospheric pressure is needed to raise temperatures enough to allow for stable liquid water.