20
A, A
negative
B, B
negative
C, C
negative
D, D
negative
E, E
negative
F, F
negative
G, G
negative
H, H
negative
I, I
negative
J, J
negative
K, K
positive
L, L
negative
Z, Z
negative
Y, Y
negative
X, X
positive
W, W
negative
V, V
negative
U, U
negative
T, T
negative
S, S
positive