1-F=ma , F=1/2 W, W=mg
v=x/t
from all these we get:
a=1/2 g =9.8/2
; a=v/t
F:force, W:waight, m: mass, a:acceleration, g: gravity acceleration, v: velocity, t: time, x:displacement
2- W= F. x cos(theta) =(30)(40) cos (60)
W:work, F: fource, x: displacement