The balls have the same mass but the table-twnnis ball is much less dense then the golf ball.
In order for <em>F</em> to be conservative, there must be a scalar function <em>f</em> such that the gradient of <em>f</em> is equal to <em>F</em>. This means


Integrate both sides of the first equation with respect to <em>x</em> :

Differentiate both sides with respect to <em>y</em> :

But we assume <em>g</em> is a function of <em>y</em>, which means its derivative can't possibly contain <em>x</em>, so there is no scalar function <em>f</em> whose gradient is <em>F</em>. Therefore <em>F</em> is not conservative.
Shauna is 65 inches and ryan is 75
75+65 = 140
3 CD → $29.98
29.98 - 6.44 = 23.54 → remained
If each CD costs the same amount ... ↓
23.54 ÷ 3 = 7.8466
$7.8466