Six people - A, B, C, D, E, and F - were born in different years: 1969, 1976, 1983, 1989, 1996, and 2010 (not necessarily in this order). Consider the base year for calculating ages as 2023. Thus, the ages are 54, 47, 40, 34, 27, and 13 years. Given conditions: - The age of A is a multiple of 9. - The difference between the ages of A and B is 14 years. - The sum of the ages of C and E is 81 years, and C was born before E. - The age of C is equal to the sum of the ages of E and F. What is the age of D?

Seven boxes A, C, G, H, J, N, and R are kept one over the other but not necessarily in the same order. Only three boxes are kept above N. Only one box is kept between H and N. Only three boxes are kept between H and A. A is kept at some place above N. R is kept immediately below A. C is kept at one of the places above G. J is not kept immediately above or below H. How many boxes are kept above H?

Seven boxes, G, H, I, J, O, K, and L, are kept one over the other, but not necessarily in the same order. Only I is kept above O. Only G is kept between O and K. Only J is kept below L. How many boxes are kept between H and J?