Help :( i don’t understand

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.

Who determined the nature of chemical bonds?

How many moles of potassium are needed to react completely with 12.8 moles of magnessium bromide?