Question

An object thrown upwards and rise to a height of 10 m calculate (a) the velocity with thrown upwards and (b) time taken by the object to reach the highest point

Answer 1

Its simple! 
Using Equation Of Motion v^2=u^2+2as ,you get 
0 = u^2+2*(-9.8)*10 (v will be zero and acceleration due to gravity will be -ve) 
so we get -u^2 = -196 
u = 14.07m/s^2 something 

for second part 
v = u+at 
0 = 14.07 + (-9.8)*t 
t = 14.07/9.8 
t = 1.43 sec