Answers for both boxes please

Which is an equation for the nth terms of the sequence 12,15,18,21

The interior angles formed by the side of a hexagon have measures of them up to 720° what is the measure of angle a

How many heads would you expect if you flipped a coin twice? first, fill in the table below with the correct probabilities. hint: the sample space for flipping a coin twice is {hh, ht, th, tt}. a = b = c = f