Image attributions - Goat - https://cdn.pixabay.com/photo/2014/04/03/00/35/goat-308775_960_720.png
- Zebra - http://maxpixel.freegreatpicture.com/static/photo/1x/Animal-Face-Wild-Head-Zebra-Eyes-Happy-Funny-37396.png
- Elephant - http://maxpixel.freegreatpicture.com/static/photo/1x/Head-Wildlife-Gray-Stupid-Zoo-Cartoon-Elephant-308776.png
- Sheep - http://maxpixel.freegreatpicture.com/static/photo/1x/Cartoon-Animal-Round-Farm-Eating-Lamb-Face-Sheep-47527.png
- Hippo - https://cdn.pixabay.com/photo/2014/04/02/16/21/hippo-307015_960_720.png
- Cow - https://cdn.pixabay.com/photo/2012/04/16/11/21/cow-35561_960_720.png