P
A
≈
1
3
.
5
9
P
A
'
≈
2
.
7
1
R
≈
7
.
2
1
P
Q
≈
2
.
5
5
P
A
×
P
A
'
≈
3
6
.
7
9
2
R
×
P
Q
≈
3
6
.
7
9