20 POINTS! PLEASE HELP ASAP! WILL GIVE BRAINLIEST! Suppose the x-axis of a density graph represents someone's age in years. If the area under the density graph from 10 years to 70 years is 0.85, what is the probability of someone's age being anywhere from 10 years to 70 years? O A. 93% OB. 85% C. 77% O D. 61% SUBMIT​

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

Ebuka's monthly rent is $750. if ebuka pays the rent late, his landlord charges 4% interest per week that the payment is late. write a function that gives the total cost r(t), in dollars, of ebuka's rent if he pays it t weeks late.

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?