First thing you have to do is change your coordinate system so that you’re perpendicular with the surface. So your weight vector will have a horizontal and vertical component. I’m going to try to do this in my head. I usually make a free body diagram. So we only want the horizontal net force because we aren’t asked about the vertical. The horizontal component of the weight vector would be opposite of the angle. So you’re gonna have to use sine instead of cosine.
Wx = W*sin(230)
To find the weight, multiply the mass by gravity. It will be 9.8N
Wx = 9.8N*sin230
Wx = -7.5i
The weight component is the only force on system, horizontally.
So do -7.5N = 1kg(a)
a = -7.5m/s^2
And you should know that acceleration is equal to the velocity over time.
-7.5 = Velocity/2s
Velocity = -15m/s
Again, sorry if I’m wrong. Did this all in my head