What is two facts can you double to find 8 x 4

Passengers usually start to board their flights 1 hour before the scheduled take off time. the gate will be closed 15 minutes before the takeoff time. jack’s plane is scheduled to take off at 12: 05 a.m. if he arrives at the gate at 11: 45 p.m., can he board the flight?

Somone me i want to know what 18 hours out of 24 hours in a fraction

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)