The position time graph for an object moving with constant acceleration starts off with a positive slope. At later times the slope becomes negative. Is the initial velocity of this object positive, negative, or zero?

Is the acceleration positive, negative or zero?

Aprisoner is forced to go into one of three rooms, but he can choose which room. the first room is ablaze with fire. the second one is rigged with explosives that will go off as soon as he enters. the third contains a pair of lions who haven't eaten in years. which room should he choose to survive?