Please teach me how to calculate the area of this circular sector.

It's difficult to solve this formula.

Vitamin D3 is an important nutrient for bone health.

I like making sandwiches.

Traffic cones have been set up due to road construction.

Amphoteric oxides have the characteristic of reacting with both acids and bases.

In chemistry class, I learned about the reactions of acid anhydrides.

In chemistry class, I learned about basic oxides.

Acidic oxides react with water to produce acids.

Aluminum is an amphoteric oxide, it reacts with both acids and bases.