Answer:
120°; 240°
Step-by-step explanation:
Let's first solve for 
: 
At this point it's just a matter of drawing a circle, and mark where the angle is(please excuse my paint skills, but free hand drawing would be even worse). Red line, is 
on the cosines, and both the green and blue lines are valid solutions. The green line is a quarter of a circle, plus 30°, or 120°. The blue one is 3/4 of a circle, minus 30 degrees, or 240°.
Answer:
True
Step-by-step explanation:
1) Type of motion: constant acceleration.
2) acceleration, a = 9.8 m/s^2
3) time up = time down = 4seconds / 2 = 2 seconds
4) formula = Vf = Vo - a*t^2/2
Vf = 0 => Vo = a*t^2 / 2 = 9.8m/s^2 * (2 s)^2 / 2 = 19.6 m/s
Answer: 19.6 m/s
5,456 I just did this question good luck
