A
B
Ct1
D0t1
7
A B C D
8 a b
c abc
A va < v b < v c
B Ta = Tc > T b
C aa > a b > a c
D abc
9
R T
ABCD
10
A.
B.
C.
D.
11 m h H
H
AmgH B mgh C mgHh D mgH-h
12 PQ ABPQ A
P 90%
