Find the next three terms (terms a_2 a_3 a_4) of the recursively defined sequence a_k = a_k-1 + 3k, for all integers k greater than or equal to 2, where a_1 = 1.

Germaine walks at the rate of 10 feet every five seconds while nolan walks at the rate of 15 feet every five seconds. if germaine has a head start of 25 feet, how many seconds will they be at the same spot?

Me with this one question, and i'll upvote the brainliest answer

Atriangular field has sides of lengths 21, 39, and 41 yd. find the largest angle. (round your answer to the nearest degree.)