If mass-energy equivalence is taken into account,when water is cooled to form ice,the mass of water should

The proposition $(\sim p) \vee (p \wedge \sim q)$ is equivalent to:

Match the following:
| Column $I$ | Column $II$ |
| :--- | :--- |
| $A$. Hooke's law | $1$. Tangential strain |
| $B$. Shearing strain | $2$. Temporary loss of elastic property |
| $C$. Bulk strain | $3$. Elastic limit |
| $D$. Elastic fatigue | $4$. $3$ times the linear strain |

The period of $\sin ^4 x + \cos ^4 x$ is

The temperature of the system decreases in the process of

If $a, b, c$ are unit vectors and the maximum value of $|a-b|^2+|b-c|^2+|c-a|^2$ is $k$,then $k(2|a|^2+3|b|^2-4|c|^2)=$