What number increased by 80% is 90?

What is the common difference for this arithmetic sequence? -6,-2,2,6,10 a.4 b.5 c.3 d.6

The bottom of a slide at the playground is 6 feet from the base of the play set. the length of the slide is 10 feet. how tall is the slide. 11.66 feet 10 feet 6 feet 8 feet

Carli has 90 apps on her phone. braylen has half the amount of apps as theiss. if carli has three timesthe amount of apps as theiss,how many apps does braylen have? let b represent the number of braylen's apps and t represent the number of theiss's apps.