Answer:
9N
Explanation:
static friction=normal force x coefficient of static friction
so static friction =30N x 0.3= 9N
The force the box is exerting on Manuel is the weight of the box, downward:

and this force is perfectly balanced by the constraint reaction applied by Manuel's hand, pushing upward.
Answer:
A) Although the speed is the same, the direction has changed. Therefore, the velocity has changed.
Explanation:
The nebular hypothesis is the name of the theory where gravitational attraction caused bits of matter to collapse, eventually forming a solar system.
Hope this helps :)