Idk about number 4 but I think the other ones are correct
Compound percentage reduction can be calculated by multiplying the initial number by (1-x)^t where x is the percentage reduction (/100, i.e. 1% reduction is 0.01), and t is the number of times it has reduced.
So:
a)
![p=45(1-0.06)^t=45*0.94^t](https://tex.z-dn.net/?f=p%3D45%281-0.06%29%5Et%3D45%2A0.94%5Et)
Where t is the number of weeks.
We can then just substitute in to work out the final pressure:
b) p = 45*0.94^6 =
31psi
The chemical formula for water is H2<span>O which means that every </span>molecule<span> of water has 2 </span>atoms<span> of hydrogen (H) and one </span>atom<span> of oxygen (O). Here comes the key part. From the Periodic Table of Elements, one sees that one mole of hydrogen </span>atoms weighs <span>1 gram while one mole of oxygen </span>atoms<span> weighs 16 grams.</span>