$300 \text{ g}$ of water at $25^{\circ} \text{C}$ is added to $100 \text{ g}$ of ice at $0^{\circ} \text{C}$. The final temperature of the mixture will be (in $^{\circ} \text{C}$)

Which of the following is not correct?

The electric current $i$ in the circuit shown is (in $A$)

Two waves $Y_1 = 0.25 \sin 316 t$ and $Y_2 = 0.25 \sin 310 t$ are propagating in the same direction. The number of beats produced per second is

If $A$ is a non-zero square matrix of order $n$ with $\operatorname{det}(I+A) \neq 0$ and $A^3=O$,where $I$ and $O$ are the unit and null matrices of order $n \times n$ respectively,then $(I+A)^{-1}$ is equal to

If $1$ is a multiple root of order $3$ for the equation $x^4-2x^3+2x-1=0$,then the other root is