Acceleration and speed????

Question

can someone heLp me soLve this physics problem???

1. a box is sliding down a plane inclined at an angle of 20° from the horizontal. find the acceleration of the box, neglecting friction and air resistance.

a. 0.342m^2g

b. 0.342 m

c. 0.342 g

d. 0.342 mg

e. 0.940m^2g

f. 0.940m

g. 0.940g

h. 0.940mg

2. a box that is hurled up the inclined plane of question 1 starts up the plane with an initial velocity of 1000cm/sec. find the speed of the box moving uo the plane 3 sec later.

a. 0 cm/sec

b. -5.5 cm/sec

c. 8.9 cm/sec

d. 10.1 cm/sec

e. 42.5 m/sec

f. 63.3 cm/sec

g. 75.3 cm/sec

h. 98.1 cm/sec

thanks for the ppl that will heLp!!!^_^

Answer 1

1. sin(20.0°) = 0.342 g

2. vf = vi + at = 1000 cm/s - (980 cm/s² x 3 s) = -1940 cm/s