Answer: 1.95
Explanation:
You should start off from the decay formula and solve for τ:


Apply inverse logarithmic function:

The final form will be:

Inputing values for I, IO, and t:
Answer:
D. Freezing?
Explanation:
Get water, put it in the freezer, turns into ice after a few hours.
Answer:
The electron cloud
Explanation:
Metallic bonds result from interaction of positively charged metal ions with free valence electrons which now forms an electron cloud around the metal ions. Electrostatic interaction between the metal ions and the electron cloud holds the metal ions together in the metallic bond.
Answer:
The enthalpy of fusion of a substance, also known as heat of fusion, is the change in its enthalpy resulting from providing energy, typically heat, to a specific quantity of the substance to change its state from a solid to a liquid, at constant pressure.