How could an indicator be used to find out something is acidic or alkaline if the label was missing?

An occluded front moves over the farmland that has been experiencing drought conditions. what change in weather will this front likely bring? a. gray skies, but no rain b. an extended period of rain c. more dry air and sunny skies d. violent, short-lived thunderstorms

The compound methyl butanoate smells like apples. its percent composition is 58.8% c, 9.9% h, and 31.4% o. what’s the empirical formula ?

Imagine that you have produced several versions of lactase, each of which differs from normal lactase by a single amino acid. describe a test that could indirectly determine which of the versions significantly alters the three-dimensional shape of the lactase protein.