Find the 10th,7th term, 8th term , 11 term and, 20th term of harmonic and sequence

By guess-and-check, identify the value/s of the variable that will make each equation true.8) |u|/2=4

The owner of a bycle store had bycles ( two-wheelers) and tricycles (three-wheelers) for sale. when he counted the toyal number of pedal of the cycles he got 66. when he counted the total of wheels on sale, he got 84. how many trycles where offered on the sale? (note: each cycle has teo pedals)

Agroup of hikers on a mountain started climbing at an elevation of 3350 feet above sea level and stopped to take their meal at an elevation of 2160 feet above sea level.a. what was the change in elevation between the two points? b. based on the answer on a,were the hikers going up or down the mountain? ​pls. help me po