Since Tina is sliding down on an inclined ramp
Net force along the inclined

Now force component on Tina perpendicular to inclined plane

now we know that normal to the inclined plane the force is counter balanced by the normal force
So we can find the normal force as

now in order to find the friction force we can write


now along the inclined plane net force is given as


also by Newton's II law we can write

by above two equations we can write




so acceleration will be 4.06 m/s^2