Why is urine yellow in colour?

Name the following: Component of urine that gives it yellow colour.

Human urine is pale yellow colour due to presence of

The……..wire is either yellow or green in colour.

The xanthophyll responsible for yellow colour of autumn foliage is

Find the values of the resistors with the following colour code: Green, White, Yellow, Gold

Find the values of the resistors with the following colour code: Grey, Red, Yellow, Silver.

Find the value of resistances for the following colour code. Yellow Violet Brown silver

When ZnO is heated it turns yellow and returns back to original white colour on cooling. What could be the reason?