Step 1:

(1)

The standard angle is $\"\"$ .

Reference angle:

If $\"\"$ be an angle in standard position, its reference angle is the acute angle $\"image\"$ formed by the terminal side of $\"\"$ , and the horizontal axis.

if $\"\"$ in First quadrant then $\"\"$ .

$\"\"$

The reference angle is $\"\"$

(2)

The standard angle is $\"\"$ .

Reference angle:

If $\"\"$ be an angle in standard position, its reference angle is the acute angle $\"image\"$ formed by the terminal side of $\"\"$ , and the horizontal axis.

if $\"\"$ in Fourth quadrant then $\"\"$ .

$\"\"$

The reference angle is $\"\"$

(3)

The standard angle is $\"\"$ .

Reference angle:

If $\"\"$ be an angle in standard position, its reference angle is the acute angle $\"image\"$ formed by the terminal side of $\"\"$ , and the horizontal axis.

if $\"\"$ in second quadrant then $\"image\"$ .

$\"\"$ \ \ The reference angle is $\"\"$

(4)

The standard angle is $\"\"$ .

Reference angle:

If $\"\"$ be an angle in standard position, its reference angle is the acute angle $\"image\"$ formed by the terminal side of $\"\"$ , and the horizontal axis.

if $\"\"$ in second quadrant then $\"\"$ .

$\"\"$ \ \ The reference angle is $\"\"$

Solution:

Reference angles are,

(1) $\"\"$

(2) $\"\"$

(3) $\"\"$

(4) $\"\"$