Consider a market with an incumbent firm I and a new entrant E producing a homogenous product and competing in quantities. The incumbent has a technology with cost function Cr(q) = 20q while the entrant produces with CE(q) = 10q. The inverse market demand is given by P(q) = 240 - q. Suppose the entrant is credit-constrained and had to repay an amount of D = 1600 at the end of the period. If the entrant is not able to cover this amount with his profits, the firm has to leave the marketplace. What is the minimum quantity qr that makes sure that the entrant is unable to repay the amount of D = 1600