6. [10] Lorianne is studying for two different exams. Because of the nature of the course, the measure of study effectiveness on a scale from 0 to 10 for the first course is E1 = 0.6(9 + te zo), while the measure for the second course is E2 = 0.5(10 + teio). Lorianne is prepared to spend up to 30h, in total, studying for the exams. The total effectiveness is given by f(t) = E1 + E2. How should this time be allocated to maximize total effectiveness? 7. [10] A variation of a triathlon competition has a contestant swimming from a point, A, on one shore of a lake, to a point C on the opposite parallel shore, then running to the finish, B, further along the lakeshore. The lake is 4km wide and the finish line is 10km down the lake. If a contestant can swim at 2km/h and run at 10km/h, determine the point C that will minimize the total time for the race.