Suppose the demand for premium bottled water increases rapidly during​ 2018. At the same​ time, six more firms begin producing premium bottled water. A student remarks​ that, because of these​ events, we​ can't know for certain whether the price of premium bottled water will rise or fall. The​ student's remarks​ (that, because of these​ events, we​ can't know for certain whether the price of premium bottled water will rise or​ fall) is