In a small european country, it is estimated that changing the level of capital from $8 million to $10 million will increase real gdp from $2 million to $3 million. what level of gdp would you expect the economy to be able to reach if spending on capital continued to rise to $12 million, assuming no technological change and no change in the hours of work? a) gdp would increase further, but by less than $1 million b) gdp would increase further by exactly $1 million c) gdp would increase further by exactly $4 million d) gdp would increase further by more than $1 million