(1) Even today, you will find a few hill tribes in Madhya Pradesh, whose faces resemble monkeys. But they don't have tails.
(2) Ravana with ten heads represents the ten organs of senses and organs of action. Eyes, ears, nose, tongue, skin, hands, legs and so on. It has a symbolic meaning. It does not mean that he really had ten heads.
(3) Kumbhakarna used to sleep for a long duration and wake up for a long duration. This is perfectly possible even scientifically proved. But, again this has a symbolic meaning. A person who sleeps too long and is lazy does evil things when he wakes up.
(4) They were not mere "arrows". They were weapons.
This is a proof that several thousands of years ago, a great culture lived in India, when the rest of the world lived a stupid, primitive life.
You people were also part of that culture, but you now walked away and embraced idiotic desert religions.