Most modern cars have designs that weigh less and can be built more cheaply.

In my opinion, the correct answer is unibody designs. As opposed to body-on-frame design, a unibody means that the car's body is not separated from the chassis, and there is no need to support it with additional (heavy) parts. They are integral, which reduces the weight of the car, and naturally results in a smaller price. 

Kyana is high in the "s" intelligence according to myers-biggs

Combining the emissions released by fossil fuel burning and  the carbon released via land use change, we get a total of 8.7 gt. since the problem states that the oceans "take up" or sequester  2.4 gt carbon  per year, we subtract that value from 8.7 gt, leaving us with 6.3 gt of carbon. since the problem states that 3.4 gt carbon dioxide emissions end up in the atmosphere, the "missing sink" of carbon takes up 2.9 gt, a value we got by subtracting the 3.4 gt amount recorded from the 6.3 gt carbon left available after the oceans sequester the carbon dioxide.