having a hard time understanding the total size part. please explain it. Solve by hand please.

Practice Problem 3.44 (solution page 381 ) For each of the following structure declarations, determine the offset of each field, the total size of the structure, and its alignment requirement for x8664 : A. struct P1 \{ short i; int c; int j; short d; \}; B. struct P2 \{ int i[2]; char c[8]; short s[4]; long j;}; C. struct P3 \{long w[2]; int c[2]}; D. struct P4 \{ char w [16] ; char *c [2] \}; E. struct P5 \{ struct P4 a [2]; struct P1 t\}