Ibhodi yokugquma i-polyurethane into enjalo kwinkqubo yokuveliswa kwemveliso iya kuba neentlobo ezahlukeneyo zokusebenza kokugquma, kwaye le nto kwimveliso yexesha, kufuneka sibe nokuqonda ngakumbi inkqubo yabo, emva kwayo yonke into, ukuqonda inkqubo, ukusinceda ukukhetha okungcono. i...
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