Can i have help please

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Which equation represents a direct linear variationa. y=x2b. y=2/5xc. y=1/xd. y=x+3

In a right triangle δabc, the length of leg ac = 5 ft and the hypotenuse ab = 13 ft. find: b the length of the angle bisector of angle ∠a.