QUESTION: answer this: name the single cell from where life begins in all sexually reproducing organisms??

ANS: zygote

QUESTION: answer this: when was the system of measuring calories invented??

ANS: 1780

QUESTION: answer this: who is the death angel in the bible??

ANS: The Destroying Angel

QUESTION: answer this: who is credited with performing the first heavier-than-air flight??

ANS:
The Wright brothers