(Q).
Q: In birds, modified front legs are actually what? Choices: - tails - arms - claws - wings A:
(A).
wings

(Q).
Q: Fuels according to the law of what, can never actually be "consumed"; it can only be changed from one form to another? Choices: - use of energy - expansion of energy - difference of energy - conservation of energy A:
(A).
conservation of energy

(Q).
Q: Varicose veins are veins that become enlarged because the valves no longer do this? Choices: - shrink properly - open properly - enlarge properly - close properly A:
(A).
close properly