Which A, B, C, OR D ?

Write the chemical symbols for three different atoms or atomic cations with 27 electrons. asap!

Imagine that twenty i.u.’s of enzyme z were catalyzing the above reaction for one minute, under vmaxconditions, in a 3.00 ml assay volume. the assay is buffered with 20 mm phosphate buffer, ph 7.60. what will the ph be at the end of that one minute?

Compare and contrast refraction of light and sound will give brainliest