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Can someone explain to me how to do

The value, v, of kalani’s stock investments over a time period, x, can be determined using the equation v=750(0.80)^-x. what is the rate of increase or decrease associated with this account? 20% decrease 20% increase 25% decrease 25% increase

Ataxi company charges $3 for pick-up plus $0.65 for each mile. select the expressions that represent the cost in dollars for a taxi pick-up and m miles. mark all that apply.