Consider 2u t2 = c 2 2u x2 + 2u y2 k u t with k > 0. (a) Give a brief physical interpretation of this equation. (b) Suppose that u(x, y, t) = f(x)g(y)h(t). What ordinary differential equations are satisfied by f, g, and h?

Exam1 Review MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Provide an appropriate response. 1) The table below shows the number of new AIDS cases in the U.S. in each of the years Classify the study as either descriptive or inferential. 1) _______ A) Descriptive B) Inferential 2) The table below shows the average income by age group for the residents of one town in the year 1998. The average incomes for each age group are estimates based on a sample of size 100 from each group. Classify the study as either descriptive or inferential. 2) _______ A) Descriptive B) Inferential Answer the question. 3) A magazine publisher mails a survey to every subscriber asking about the quality of its subscription servi