62/63/64 thanks

Math 1P97 Final Examination July 2011 page 16 of 16 62. Which is the best differential equation for the following statement? " The rate of change of length of grass G, is proportional to the difference between the noon temperature and 15 degrees." (Assuming it is summer and the temperature always goes above 15 degrees.) a. do _ KT di dG b. T - 8 dG = (k - 8)T d. d1 = k(T + 8) di dG -= k(T -8) Solve the separable differential equation dy _4x dx X(1)= 3 in two steps as follows. 63. When the differential equation is solved and in the form of y? =.....+ (', what is C? a. b. 3 C. 4 d. 5 e. none of the above 64. Find v(2) a. 11 b. 9 C. 3 d. 3.32 e. 4.58