At a birthday party, 5 boys and 3 girls are seated in a row. How many different arrangements are possible if: the leftmost and rightmost end seats are occupied by boys, and no girls are seated next to each other?
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Aquantity with an initial value of 3900 decays exponentially at a rate of 35% every hour. what is the value of the quantity after 0.5 days, to the nearest hundredth?

If np3 /nc2 = 6, find the value of n

Acentral angle measuring 160 degrees intercepts an arc in a circle whose radius is 4. what is the length of the arc the circle formed by this central angle? round the length of the arc to the nearest hundredth of a unit. a) 4.19 units b) 6.28 units c) 12.57 units d) 12.57 square units