"rock" concert

Fig. 1
Fig. 2
Fig. 3

Fig. 4

Yihui's rock concert performance. Her band (Brown Cow Entourage????) is rocking hot, especially the vocalist. But let's check out on Yihui too.

Fig. 1 is the band playing "Bring Me To Life" by Evanescence.
Fig. 2 is the band playing "Don't Look Back In Anger" by Oasis.
Fig. 3 is the band playing "Zombie" by The Cranberries.
Fig. 4 is a close up shot of Yihui after all the performances.

Q1:
State the differences and similarities in Yihui from Fig. 1 to 4.
Nothing different and they're similar throughout.
Q2:
Account for the trend spotted in Fig. 1 to 4.
No difference = no trend.
Q3:
Give explanations to your answer in Q2.
Errrrrr..... Maybe because it's a "rock" concert?