1) A 1kW lifting motor lifts a pallet with a piano on it (400kg total) 15m up to a 4th floor apartment window. How long does it take to lift the piano if the motor can use all of its power?​

The particle p starts from rest at point a at time t = 0 and changes its speed thereafter at a constant rate of 2.8g as it follows the horizontal path shown. determine the magnitude and direction of its total acceleration (a) just before point b, (b) just after point b, and (c) as it passes point c. state your directions relative to the x-axis shown (ccw positive) and choose the angle with the smallest magnitude.