Answer:
25 (with assumptions)
Step-by-step explanation:
ASSUMING ES=SD and FT=TG, then the difference between EF and ST is the same as the difference between ST and DG. Since ST - EF = 19 - 13 = 6, then DG - ST = 6 or DG - 19 = 6, add 19 to both sides and DG = 25
