Question: "I Ai n't Mad at Cha" is a song by rapper 2Pac released shortly after his death as the sixth single from his album All Eyez on Me. It was also his last single using the stage name 2Pac. The song features contemporary soul singer Danny Boy who provided the vocals for the song's hook. The song did well in the United Kingdom, reaching the number 13 on the UK Singles Chart and on the UK R&B Charts peaking at number 3. It was not released as a single in the United States, thus making it ineligible to chart on the Billboard singles charts (due to chart rules at the time), but reached numbers 18 and 58 in the R&B and Pop Airplay charts, respectively. It also reached number two on the New Zealand Singles Chart.

Answer this question based on the passage: who sings on i ain't mad at cha?
Answer: To answer the above question, the relevant sentence is: The song features contemporary soul singer Danny Boy who provided the vocals for the song's hook. The answer is Danny Boy.

Question: Context: A regular octagon is a closed figure with sides of the same length and internal angles of the same size. It has eight lines of reflective symmetry and rotational symmetry of order 8. A regular octagon is represented by the Schlafli symbol (8). The internal angle at each vertex of a regular octagon is 135 (3 4 ( \ displaystyle \ scriptstyle ( \ frac ( 3 \ pi) (4) ) ) radians ). The central angle is 45 ( 4 ( \ displaystyle \ scriptstyle ( \ frac ( \ pi) (4) ) ) radians ).

Question: how many lines of symmetry in an octogon?
Answer: To answer the question, consider the following: It has eight lines of reflective symmetry and rotational symmetry of order 8. The answer is eight.

Question: Context: Charlene Amoia is an American actress best known for her role as Wendy the waitress in the TV sitcom How I Met Your Mother. Some of her other television credits include Glee and Diana Coto on Switched at Birth, and her film credits include Kevin's (Thomas Ian Nicholas) wife Elllie in American Reunion (2012) from the American Pie series.

Question: who plays wendy the waitress on how i met your mother?
Answer: The relevant information to answer the above question is: Charlene Amoia is an American actress best known for her role as Wendy the waitress in the TV sitcom How I Met Your Mother. The answer is Charlene Amoia.

Question: "It All Started with a Beer" is a song recorded by American country music artist Frankie Ballard. It was released in November 2015 as the first single from Ballard's third studio album, El Rio. The song was written by Jaren Johnston, Neil Mason and Jeremy Stover.

Who sings it all started with a beer?
Answer:
To answer the question, consider the following: "It All Started with a Beer" is a song recorded by American country music artist Frankie Ballard. The answer is Frankie Ballard.