A consulting firm has come up with an estimate of the TB and TC from expanding Mizner Park, here in Boca Raton. The TB numbers for Q = 1, 2 & 3 city blocks, are $13,333, 25,666, 36,999, respectively. The TC numbers are $6,939, 13,878, 20,817. In this case, the MB is ____ and the MC is ____.
\text{O}decreasing; constant
\text{O}decreasing; increasing
\text{O}constant; increasing
\text{O}constant; constant