Anybody? Geometry help using Angle Sum Theorem

What is the 17th term in the arithmetic sequence in which a6 is 101 and a9 is 83

In δabc, m∠acb = 90°, cd ⊥ ab and m∠acd = 45°. find: a find cd, if bc = 3 in

Grandpa ernie is shrinking! over the past 4 years his height decreased by a total of 2.4 cm.it decreased by the same amount each year. what was the change in grandpa ernie's height each year