If jill starts out at 20 m/s, and in 10 s speeds up to 40 m/s, what is her acceleration?
o 3 m/s2
o 200 m/s2
02 m/s2
01 m/s2

Explanation:

The acceleration of an object (or a person, as in this case) is given by

where

v is the final velocity

u is the initial velocity

t is the time interval

In this problem,

u = 20 m/s

v = 40 m/s

t = 10 s

Therefore Jill's acceleration is

The acceleration of Jill is if he starts out at the velocity 20 m/s and in 10 s speeds up to 40 m/s.

From given, we came to know that the Jill starts out at 20 m/s, and in 10 s speeds up to 40 m/s, to find acceleration of Jill, we know that acceleration is ratio of velocity to time change.

The acceleration is given by the formula:

We know that change in velocity as 20 m/s to 40.0 m/s and change time as 10 s.

Thus, acceleration of Jill will be

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