If you are given values for Δx, v, and Δt, which kinematic equation could be used to find v0?​

Question

V = v0 + aΔt
Δx= (v + v0/ 2) Δt (THIS ONE?)
v^2 = v0^2 + 2aΔx
Δx = v0Δt + 1/2 a (Δt)^2

For horizontally-launched projectiles which of the following describes acceleration in both directions with ax = 0 and ay = -9.8 m/s^2

acceleration is zero in both directions
acceleration is equal in both directions
acceleration is -9.8 m/s^2 in both directions
acceleration is constant in both directions THIS ONE

Answer 1

Δx= (v + v0/ 2) Δt (THIS ONE?)========== yes
acceleration is constant in both directions THIS ONE ======== yes