please solve quickly

Using this model for projectile motion: 7 (t) - - ((vocose)t. n + (vosine)t- or2 ) . to find the maximum height attained by a projectile, you would start by: O Setting x(t) = 0 and solving for t ( Setting y(t) = 0 and solving for t O Setting x'(t) = 0 and solving fort O Setting y'(t) = 0 and solving for t O None of these