Question

If triangle RST is an acute triangle, then m∠S must be

less than 90°.
equal to 90°.
equal to 100°.
greater than 90° and less than 180°.

Answer 1

Less than 90 degree

Explanation:

Because acute triangles are less than 90 degree.

And an acute triangle only include acute angles, no right angles (equal 90 degree) or obtuse angles (greater that 90 degree and less than 180 degree).

So... the answer is less than 90°! less than 90°! less than 90°! A! A! A!

Cheers! (￣▽￣)～■□～(￣▽￣)

Answer 2

less than 90°

Explanation:

Acute angles are less than 90°