(Q).
Q: What important and unusual physical property (for birds) do ostriches and penguins share? Choices: - waterproofness - webbed feet - bonelessness - flightlessness A:
(A).
flightlessness

(Q).
Q: What type of animal that eats only or mainly insects? Choices: - anaerobic - invertebrates - herbivores - heterotrophic A:
(A).
heterotrophic

(Q).
Q: What is caused by bodies sliding over rough surfaces? Choices: - heat loss - tension - vibration - friction A:
(A).
friction