'Whether' in the Bible

And who knows whether he will be a wise man or a fool? Yet he will have control over all the fruit of my labor for which I have labored by acting wisely under the sun. This too is vanity (futility, self-conceit).

Who knows if the spirit of man ascends upward and the spirit of the animal descends downward to the earth?

The sleep of a working man is sweet, whether he eats little or much; but the full stomach (greed) of the rich [who hungers for even more] will not let him sleep.

Whatever exists has already been named [long ago], and it is known what [a frail being] man is; for he cannot dispute with Him who is mightier than he.

For I have taken all this to heart, exploring and examining it all, how the righteous (those in right standing with God) and the wise and their deeds are in the hands of God. No man knows whether it will be love or hatred; anything awaits him.

Sow your seed in the morning and do not be idle with your hands in the evening, for you do not know whether morning or evening planting will succeed, whether this or that, or whether both alike will be good.

For God will bring every act to judgment, every hidden and secret thing, whether it is good or evil.