Idon't understand this question can someone explain how you would solve this?

What molecule does hemoglobin decay into over time

Do the following statements describe actin, myosin, both of the proteins or neither of the proteins? (a) contains a binding site for calcium (b) found in the i band (c) exists in a globular (g) form and a filamentous (f) form (d) contains a binding site for atp (e) is a component of the thin filament (f) is a component of the thick filament

What does the number 18.9984 represent in the image?