Choose the word that is closest in meaning to esoteric
The scientist's theory was initially met with _________, but later gained widespread acclaim after consistent experimental validation.
A particle is moving in a straight line. The variation of position $ x $ as a function of time $ t $ is given as: $ x = t^3 - 6t^2 + 20t + 15 $. The velocity of the body when its acceleration becomes zero is: