Hello, I want to know that 1. L-ascorbic acid Fine and Ultra grades, when used to make serum in the same %, are they equivalent? ?? 2. L-ascorbic acid If using 1% ActiveUV and 1% ActiveOX is sufficient to maintain the efficacy. วิตามินซี ?? or should choose to put Ferulic Acid and วิตามินอี added to...