100 megatons+234 help please

Solve the system of equations. y= 2x y= x^2 - 15

Fred has a spinner that is split into four equal sections: red, blue, green, and yellow. fred spun the spinner 688 times. which of the following would be a good estimate of the number of times the spinner lands on the green section? a. 269 b. 603 c. 344 d. 189

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?