Moles Pbl2 = 0.8628 g : 461.01 g/mol = 0.001871
moles I = 2 x 0.001871 = 0.003742
[I-] = 0.003742/ 0.0429
= 0.0872 M
We know that in physics the momentum of an object is defined as the product of mass by the velocity of the object.
That is to say:
Where P is the momentum = 
kilograms meters/second
m is the mass
v is the object velocity = 30 m/s
In this problem we have the momentum of the roller coaster and its speed, but we want to find its mass. Then we divide the momentum between speed.
The mass is 833.33 kg
Answer:
Iris
Explanation:
The iris seems to be the illuminated portion of the eyes which really covers the pupil. It controls the amount of light reaching the eye. The lens is indeed a translucent layer of the retina that serves to concentrate light and objects on the lens.
In steering in control on a PWC, the most needed requirement is to have power in which will allows the one using it to control the engine for it to stop or for it to move. Without power, the person using it could be out of balance or fail to start the engine. This is the basic requirement because even though it is shut off or the engine is off, the PWC is still on and it could still move without proper knowledge of the engine.
You should back-up your computer every few weeks (or as often as needed).
As soon as you suspect that your computer (or any other backup-able device) is too slow or "glitch-y" you should back-up your device before you lose any important files or data.
PREVENTING MALFUNCTION:
→ Always set your computer on a hard & flat surface.
→ Avoid downloading programs from unknown or non-trusted sources.
→ Avoid using your computer in a hot area.
→ Consider installing a virus/malware protection software on your computer.
