Prove that if a σ-algebra of subsets of r contains intervals of the form (a,[infinity]), then it contains all the intervals.

How many sides does a regular polygon have if each exterior angle measures 72a.3b.4c.5d.6

Arianna is buying plants for her garden. she buys 15 flowering plants for $96. pink flowering plants sell for $8, and purple flowering plants sell for $5. how many pink flowering plants did arianna buy? i figured out the answer! the answer is 7. 8x +5y = 96 plug in 7 for x 8 (7) + 5y = 96 56 + 5y = 96 subtract 56 from both sides 5y/y = 40/5 y = 8 she bought 7 pink and 8 purple plants

Harry and jay are both flying on the same plane with an airline that randomly assigns seats to passengers. of the 182 total seats on the plane, 62 are window seats, 58 are middle seats, and the rest are aisle seats. what is the approximate probability that both harry and jay will be assigned aisle seats on the same plane? a. 11.48% b. 3.3% c. 2.08% d. 26.26%