need help understanding these problems

(a) You have a styrofoam container with 900 g of orange juice (specic heat of 3,770 J/(kg ~ C)) at 29.0 and you add a 74 g chunk of ice at 0C. Assume the liquid and water mix uniformly as the ice melts and determine the nal temperature of the mixture (in C). 20.29 W c (b) what If? What is the minimum mass of the ice cube (in 9) that will result in a final mixture at exactly 0C? 36413 x g Need Help? [on Points] PREVIOUS ANSWERS SERPSE10 18.4.0P.005. PRACTICE ANOTHER The concrete sections of a certain superhighway are designed to have a length of 27.0 m. The sections are poured and cured at 10.0C. What minimum spacing should the engineer leave between the sections to eliminate buckling if the concrete is to reach a temperature of 480C? (Note: If applicable, Table 1 is available for use in solving this problem.) X Your answer cannot be understood or graded' More Information cm Need Help