While standing at the edge of the roof of a building, a man throws a stone upward with an initial speed of 6.37 m/s. How much time 't' does the stone spend in the air?
a) ( t = /{2 ⋅ 6.37}/{9.8} ) seconds
b) ( t = /{6.37}/{4.9} ) seconds
c) ( t = /{2 ⋅ 6.37}/{g} ) seconds
d) ( t = /{6.37}/{g} ) seconds