Buys a new tractor made in iowa by a german company. as a result, _______
a. u.s. investment, u.s. gdp, and german gdp all increase.
b. u.s. investment, u.s. gdp, and german gdp are unaffected because tractors are intermediate goods.
c. u.s. investment and gdp increase, but german gdp is unaffected.
d. u.s. investment and german gdp increase, but u.s. gdp is unaffected.