Drag force

An accelerometer is built into a ball and the ball is the dropped from rest. As the ball falls, the total force on the ball is the sum of the gravitational force and the frictional drag force. The gravitational force is $F_{grav}=-9.81m$ N where the mass of the ball is $m=$ g. The drag force depends on the velocity of the ball. The accelerometer measures the acceleration of the ball which is proportional to the total force, $F_{total}=ma$. The data from the accelerometer is shown below. What is the drag force when the ball is travelling at  m/s?

Integrate the acceleration to get the velocity using the numerical integration app.