1. Dlaczego emaliowane garnki rdzewieją w miejscu uszkodzenia emalii? 2. Dlaczego dachy starych budynków wykonanych z blachy miedzianej pokrywa zielony nalot. 3. Co to jest rdza? 4. Jak przeciwdziałać korozji.

potrzebuje jak najszybciej

Why do enamelled pots rust when the enamel is damaged? 2. Why the roofs of old buildings made of copper sheet are covered with green coating. 3. What is rust? 4. How to prevent corrosion.

I need it as soon as possible

i just know the translation

a: 45.9 meters

b: 4.29 seconds

step-by-step explanation:

a: h(t)=1/2(-9.8)(3)^2+0(3)+90

h(t)=-4.9(3)^2+90

h(t)=-44.1+90

h(t)=45.9 meters

b: 0=1/2(-9.8)(t^2)+0t+90

0=-4.9t^2+90

-90=-4.9t^2

18.37=t^2

t=4.29 seconds

in the second question, the numbers aren't exact, but they're a close approximation.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)