Please help im in a test rn each ice cube in the glads is a perfect cube with dimensions all 1 inch. If there are exactly 15 cubes in the glass, will the level of water be after the ice melts. the base of the glass is 3 inches.

Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b