A car accelerate from rest at a constant rate $$ \alpha $$ for some time after which it decelerate at a constant rate $$ \beta $$ to come to res. If the total time elapsed is 10 sec., then the maximum velocity reached is

A

$$ \frac{10\alpha} {\beta} $$

B

$$ \frac{10(\alpha + \beta)} {\alpha \beta} $$

C

$$ \frac{10\alpha \beta} {\alpha + \beta} $$

D

$$ \frac{10 \beta} {\alpha} $$