Acceleration is the change in the speed or direction of an object over time—in other words, acceleration is a change in an object's velocity over time. To determine the rate of acceleration, you usethe formula below. The unit for acceleration is meters per second per second ( m/s2). A positive value oracceleration shows speeding up, and negative value for acceleration shows slowing down. Slowingdown is also called deceleration

Explanation:

The acceleration of an object is equal to the rate of change of velocity. Its mathematical form is given by :

Where

v is final velocity, u is initial velocity and t is time taken

The SI unit of velocity is m/s and that of time is s. The SI unit of acceleration is

If final velocity is more than the initial velocity, acceleration is positive.

If the final velocity is less than the initial velocity, the acceleration is negative. It is also known as deceleration.

Hence, all the statement is true.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form