Confused as to what I got wrong

Question $2$

Assume that $i,t,x,y,$ and $z$ are $C++$ int variables. Refer to the table below for the variables being used and their associated registers.

Write the corresponding MIPS I instruction$($s$)$ to C$++$ code or write the instructions to perform the desired task.

i$.y=$ the sign of $\frac{x}{\frac{?}{?}}$ let y hold a pattern that numerically equals to the sign bit of x

If a constant$/$immediate is used, write type it in $2-$digit hexadecimal representation. Don't forget to use prefix $0$x$.$

Hint: Extract the far$-$left bit of variable $x$ and put it in the far$-$right position of variable $y.$ Refer to question $4$ of ${04}_{?}-$ Logical Operations.

In the comment box, write the corresponding logical expression such as $x$&$01919,x,|,01818,x>>081,$or

$1,$#$y=$

ii$.$ Preserve the bits of $x$ at odd positions that are lower than $16(1,3,5,$dots$13,15)$ while masking off all other positions. Use variable $t$ to hold the result.

If a constant$/$immediate is used, write type it in $4-$digit hexadecimal representation. Don't forget to use prefix $0$x$.$

In the comment box, write the corresponding logical expression such as $x$&$01919,x,|,01818,x>>081,$or

$1,$#$t=$

iii. Follow the two$-$step negation in here to perform $y=-z.$

If a constant$/$immediate is used, write type it in $4-$digit hexadecimal representation. Don't forget to use prefix $0$x$.$

$1$

$\frac{?}{?}$# $$2=z$

$2$

iv$.$ Review the following binary equivalents of multiples of $4.$

Write the corresponding MIPS I instruction$($s$)$ to the following C$++$ code: $y=z,8,4$;

If a constant$/$immediate is used, write type it in $4-$digit hexadecimal representation. Don't forget to use prefix $0$x$.$

Hint: Mask off the higher $30$ bits of variable $z.$ Refer to question $4$ of $04-$ Logical Operations

In the comment box, write the corresponding logical expression such as $x$&$0x1919,x,|,01818,x>>081,$or