How could one lower the glass transition temperature of a germate (GeO2) glass? Select all possible ways.

i)Increase the cooling rate.
ii)Decrease the cooling rate.
iii)Add SiO2 to the glass melt.
iv)Add CaO to the glass melt.

I, III and IIII?

I, III and IV is wrong ;)

the correct is/are ?

Which one is/are the possible ways?

tried I and III, its not correct. It can be all, II, III and IIII or somthing else??

2 and 4

Are u sure about 4?

2 an 4 are correct

Thank you Anonima

2 and 4 is right

ii)Decrease the cooling rate.
iv)Add CaO to the glass melt