A bus starts with a speed 15 metre per second then how much time does it take to complete 15 km pls pls help

The diagram shows a series of volcanic island and a hot spot determine the direction of movement of the tectonic plate that for the island

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.

When doing scientific research ,the sources used should be ?