Questions

Parabola, because when the coin is dropped at a particular point, it has the same velocity as the running train. So, by Newton's first law, it continues its motion horizontally with that velocity. But then, it is also pulled down by earth's gravity continuously. In this situation its horizontal motion gives way to the parabolic motion until it reaches the ground.

In the history, Rurik was believed to be the first ruler to consolidate the slavic tribes. He was a Russian leader in the 9th century.

PFD's : Personal Flotation Devices (life jackets).

It is a legal requirement for a PFD to

1. Must be in good, serviceable condition 

2. PFDs must be properly sized for the intended wearer.

3. Sizing for PFDs is based on body weight and chest size.

- Send the box with the lock to Alex. 

- Alex can't open it, but can put another lock on the box. 

- Alex sends this box with the 2 locks back to you, you unlock your lock and send it back to Alex again.

- So there is just Alex's lock on the box and Alex can now open it.

Longest railway bridge (Lower Zambesi ) is located in Africa