For metalloids on the periodic table, how do the group number and the period number relate?

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

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?

Once similarity and one difference between a mixture of elements and a mixture of compounds