Question

Can you help me please

Answer 1

The answer of upper level of Figure 2 IS correct

Explanation:

Actually, clockwise rotation 270° is the same as counterclockwise rotation 90°. May be it will be easier to clear out the thinking process.

Picture attached.. We can set A as the imaginary origin (0,0) to rotate.

Answer 2

figure 2

Explanation:

I used AC as my "compass".

0 degrees rotation (as the graphic) :

AC points to the right, B is up.

90 degrees rotation :

AC points straight down, B is to the right.

180 degrees rotation :

AC points to the left, B is down.

270 degrees rotation (= 90 degrees counter-clockwise) :

AC points up (C above A), B is to the left.

now this gets reflected across the y axis (that means flipped over or 3D- rotated by 180 degrees around the y axis).

so, AC still points up (and C is still above A), but B is now to the right.