When force is applied on an object the object will not slide
So here object will remain in equilibrium after applying the force
So in this case the condition of equilibrium is maintained due to friction force that is applied on the object.
So here for equilibrium be can say

also we know that

we are given that
( applied force on the box)


So here this friction force on the cart is known as static friction

Answer:1.it changes its physical state 2.lemonade 3.A mixture of 3 or more substances
Explanation:
Lemonade is a mixture.A solution is mixture of two or more substances.if changes from a solid into a different form of state